TW202109858A - Solid-state imaging device and method for producing solid-state imaging device - Google Patents

Abstract

Translated fromChinese

獲得一種即便是微細畫素亦可提升聚光效率、所有色高精細且靈敏度佳的固態攝影元件及固態攝影元件製造方法。固態攝影元件具備：半導體基板；設置在半導體基板，且在平面圖中配置成矩陣狀的複數個光電轉換元件；濾色器層，與複數個光電轉換元件分別對應配置的複數色的濾色器是按預先設定的規則圖案作二維配置；微透鏡，具有與複數色的濾色器及複數個光電轉換元件分別對應配置的複數個透鏡之微透鏡層作複數積層所形成。複數個微透鏡層中之最接近於光電轉換元件作配置的第1微透鏡層的膜厚為150nm以上400nm以下。A solid-state imaging element and a solid-state imaging element manufacturing method that can improve light collection efficiency even with fine pixels, all colors are high-definition, and have good sensitivity. The solid-state imaging element includes: a semiconductor substrate; a plurality of photoelectric conversion elements arranged on the semiconductor substrate and arranged in a matrix in a plan view; a color filter layer, and a plurality of color filters of plural colors arranged corresponding to the plurality of photoelectric conversion elements are A two-dimensional arrangement is made according to a predetermined regular pattern; the microlens is formed by a plurality of layers of microlenses having a plurality of lenses arranged corresponding to a plurality of color filters and a plurality of photoelectric conversion elements, respectively. The film thickness of the first microlens layer arranged closest to the photoelectric conversion element among the plurality of microlens layers is 150 nm or more and 400 nm or less.

Description

Translated fromChinese

固態攝影元件及固態攝影元件的製造方法Solid-state imaging element and manufacturing method of solid-state imaging element

本發明係有關一種固態攝影元件及固態攝影元件的製造方法。The present invention relates to a solid-state imaging element and a manufacturing method of the solid-state imaging element.

近年來，數位相機等所搭載的CCD(Charge Coupled Device；電荷耦合裝置)影像感測器或CMOS(Complementary Metal-Oxide-Semiconductor；互補金氧半導體)影像感測器等之固態攝影元件係日益高畫素化、微細化，特別是微細物係形成為低於1.1μm×1.1μm的畫素尺寸。In recent years, CCD (Charge Coupled Device) image sensors or CMOS (Complementary Metal-Oxide-Semiconductor; Complementary Metal-Oxide-Semiconductor) image sensors and other solid-state imaging devices mounted on digital cameras have been increasing. Pixelization and miniaturization, in particular, the fine object system is formed into a pixel size of less than 1.1 μm×1.1 μm.

固態攝影元件係藉由分別設置與複數個光電轉換元件成對的濾色器以謀求彩色化。又，設於固態攝影元件的光電轉換元件有助益於光電轉換的區域(開口部)，係與固態攝影元件的尺寸、畫素數相依存。該開口部相對於固態攝影元件整個面積受限於20%以上50%以下的程度。由於小的開口部會直接導致光電轉換元件的靈敏度降低，因此固態成像裝置通常在光電轉換元件上形成聚光用的微透鏡以補償靈敏度的降低。藉由用微透鏡將光聚光並導入光電轉換元件的受光部，可將受光部的表觀開口率設大，從而提升固態攝影元件的靈敏度。The solid-state imaging device achieves colorization by providing color filters paired with a plurality of photoelectric conversion devices, respectively. In addition, the area (opening) of the photoelectric conversion element provided in the solid-state imaging element that contributes to photoelectric conversion depends on the size and the number of pixels of the solid-state imaging element. This opening is limited to 20% or more and 50% or less with respect to the entire area of the solid-state imaging device. Since a small opening directly causes the sensitivity of the photoelectric conversion element to decrease, the solid-state imaging device usually forms a microlens for condensing light on the photoelectric conversion element to compensate for the decrease in sensitivity. By condensing light with a microlens and guiding it to the light-receiving part of the photoelectric conversion element, the apparent aperture ratio of the light-receiving part can be set large, thereby improving the sensitivity of the solid-state imaging element.

又，近年來，為改善微細畫素的靈敏度、遮蔽(shading)特性而開發有背面照射型固態攝影元件(BSI：Back Side Illumination；背光照度技術)。背面照射型固態攝影元件中，因在光的射入側無設置多層金屬配線而可將開口部設成固態攝影元件整個面積的50%以上，可有效率地將射入光取入於光電轉換元件。然而，因為要使用背面照射技術，使得光電轉換元件會存在於供固態攝影元件的光射入的表面側。因此，因為鄰接於濾色器的別的濾色器的漏洩光進入光電轉換元件、在光電轉換元件的內部被吸收的光進入鄰接的光電轉換元件、或經光電轉換而產生的電子流動於鄰接的光電轉換元件之電路部等之主要原因而變得容易發生混色。在該對策方面，作成在濾色器間形成分隔壁，利用分隔壁遮蔽光，或者分隔壁作為波導管以引導光，又，作成在光電轉換元件間亦形成深的元件分離構造，以分離電子流或在光電轉換元件內部被吸收的光(專利文獻1、2)。In addition, in recent years, back-illuminated solid-state imaging devices (BSI: Back Side Illumination; backlight technology) have been developed in order to improve the sensitivity and shading characteristics of fine pixels. In the back-illuminated solid-state imaging device, since there is no multi-layer metal wiring on the light incident side, the opening can be set to more than 50% of the entire area of the solid-state imaging device, and the incident light can be efficiently taken in for photoelectric conversion. element. However, because the backside illumination technology is used, the photoelectric conversion element is present on the surface side where the light of the solid-state imaging element enters. Therefore, because the leaked light of another color filter adjacent to the color filter enters the photoelectric conversion element, the light absorbed inside the photoelectric conversion element enters the adjacent photoelectric conversion element, or the electrons generated by photoelectric conversion flow in the adjacent photoelectric conversion element. Color mixing easily occurs due to the main reasons such as the circuit part of the photoelectric conversion element. In terms of this countermeasure, a partition wall is formed between the color filters, and the partition wall is used to shield the light, or the partition wall is used as a waveguide to guide the light, and a deep element separation structure is also formed between the photoelectric conversion elements to separate the electrons. Flow or light absorbed inside the photoelectric conversion element (Patent Documents 1 and 2).

伴隨著固態攝影元件的高畫素化、微細化，必須和光電轉換元件配成一對而形成微透鏡。因此，被要求微透鏡的形成區域的尺寸變小、微透鏡的微細化。又，在將微透鏡依照原樣進行微細化的情況，因微透鏡所致之聚光點偏移、光在微透鏡端的聚光力變差。因此，具有光照射於各濾色器間的分隔壁部分等而無法將光有效率地集中於光電轉換元件的問題。為解決該問題，在將微透鏡微細化後，必須提高微透鏡的寬高比，一邊微細化一邊控制成寬高比高的形狀，在製程上是困難的。再者，當寬高比設高時，則因鄰接的微透鏡彼此干涉而具有無法一邊維持透鏡形狀一邊微細化的問題。With the high-resolution and miniaturization of solid-state imaging elements, it is necessary to pair with photoelectric conversion elements to form microlenses. Therefore, the size of the formation area of the microlens is reduced, and the microlens is required to be miniaturized. In addition, when the microlens is miniaturized as it is, the condensing point shifts due to the microlens, and the condensing power of the light at the end of the microlens deteriorates. Therefore, there is a problem that light is irradiated on the partition wall portion between the respective color filters and the like, and the light cannot be efficiently concentrated on the photoelectric conversion element. In order to solve this problem, after miniaturizing the microlens, the aspect ratio of the microlens must be increased, and it is difficult to control the aspect ratio while miniaturizing the microlens. Furthermore, when the aspect ratio is set to be high, the adjacent microlenses interfere with each other, and there is a problem that the size of the lens cannot be reduced while maintaining the shape of the lens.

為解決此種問題，揭示使用折射率高的材料作為微透鏡的材料，在未設置微透鏡間的變平坦的空間下形成微透鏡，藉此即使是經高畫素化、微細化的固態攝影元件也能提升光的取入效率(專利文獻3)。又，揭示一種將微透鏡以複數層構造形成，藉由調整各層的膜厚以抑制靈敏度不均一的微透鏡(專利文獻4)。再者，專利文獻5中，揭示一種示出由無機材料構成的微透鏡的折射率與形成在微透鏡與濾色器之間的非平坦化層的膜厚之關係，以抑制靈敏度特性之減低的技術(專利文獻5)。[先前技術文獻][專利文獻]In order to solve this problem, it is disclosed that a material with a high refractive index is used as the material of the microlens, and the microlens is formed in the flattened space between the microlenses, thereby even the high-resolution and miniaturized solid-state photography The element can also improve the efficiency of taking in light (Patent Document 3).In addition, a microlens is disclosed in which a microlens is formed in a multiple-layer structure, and the film thickness of each layer is adjusted to suppress uneven sensitivity (Patent Document 4). Furthermore, Patent Document 5 discloses a relationship between the refractive index of a microlens made of an inorganic material and the film thickness of an uneven layer formed between the microlens and the color filter, so as to suppress the decrease in sensitivity characteristics. Technology (Patent Document 5).[Prior Technical Literature][Patent Literature]

[專利文獻1]日本特許第6052353號公報[專利文獻2]國際公開第2017/073321號[專利文獻3]日本特開2005-019573號公報[專利文獻4]日本特開2015-230896號公報[專利文獻5]日本特許第6366101號公報[Patent Document 1] Japanese Patent No. 6052353[Patent Document 2] International Publication No. 2017/073321[Patent Document 3] JP 2005-019573 A[Patent Document 4] JP 2015-230896 A[Patent Document 5] Japanese Patent No. 6366101

[發明欲解決之課題][The problem to be solved by the invention]

然而，當微透鏡使用折射率高的無機材料時，則在畫素尺寸微細化時，會有所有濾色器無法高靈敏度化的情況。例如，在微透鏡的高度高時，應射入於鄰接的畫素的射入光被微透鏡所阻斷，有受光效率降低的情況。However, when an inorganic material with a high refractive index is used for the microlens, when the pixel size is miniaturized, all the color filters may not be able to increase the sensitivity. For example, when the height of the microlens is high, the incident light that should be incident on the adjacent pixels is blocked by the microlens, and the light receiving efficiency may be reduced.

本發明係有鑒於上述各點而研創，目的在於提供一種即便是微細畫素也能使聚光效率提升且所有色為高精細且靈敏度佳的固態攝影元件及固態攝影元件製造方法。[用以解決課題之手段]The present invention is developed in view of the above points, and its purpose is to provide a solid-state imaging device and a solid-state imaging device manufacturing method that can improve the light-collecting efficiency even with fine pixels, and all colors are high-definition and high-sensitivity.[Means to solve the problem]

本發明一態樣的固態攝影元件，具備：半導體基板；複數個光電轉換元件，設於半導體基板且在平面圖中配置成矩陣狀；濾色器層，與複數個光電轉換元件分別對應配置的複數色的濾色器是按預先設定的規則圖案作二維配置；及微透鏡層，具有與複數色的濾色器及複數個光電轉換元件分別對應配置的複數個透鏡，微透鏡層具有：配置在最接近於光電轉換元件側的第1微透鏡層；及形成為積層於第1微透鏡層的透鏡面上的第2微透鏡層，第1微透鏡層係膜厚為150nm以上400nm以下、折射率為1.75以上2.15以下、且由氮化矽或氮氧化矽所形成，第2微透鏡層係由具有比第1微透鏡層還低的折射率之氮氧化矽或氧化矽所形成。One aspect of the solid-state imaging device of the present invention includes:Semiconductor substrateA plurality of photoelectric conversion elements are arranged on the semiconductor substrate and arranged in a matrix in a plan view;In the color filter layer, the color filters of the plural colors respectively arranged corresponding to the plural photoelectric conversion elements are arranged two-dimensionally according to a predetermined regular pattern; andThe micro lens layer has a plurality of lenses arranged corresponding to the color filters of the plurality of colors and the plurality of photoelectric conversion elements, respectively,The microlens layer has: a first microlens layer arranged on the side closest to the photoelectric conversion element; and a second microlens layer formed to be laminated on the lens surface of the first microlens layer,The first microlens layer has a thickness of 150 nm or more and 400 nm or less, a refractive index of 1.75 or more and 2.15 or less, and is formed of silicon nitride or silicon oxynitride,The second microlens layer is formed of silicon oxynitride or silicon oxide having a lower refractive index than the first microlens layer.

本發明一態樣的固態攝影元件的製造方法為具備：複數個光電轉換元件在平面圖中配置成矩陣狀，在將複數個光電轉換元件之間設有元件分離構造的半導體基板上的光電轉換元件包圍的位置，形成分隔壁之步驟；將複數色的濾色器分別形成在與被分隔壁包圍的光電轉換元件對應之位置的步驟；在濾色器及分隔壁的上部，形成膜厚為150nm以上400nm以下且折射率為1.75以上2.15以下的氮化矽膜或氮氧化矽膜，在與複數個光電轉換元件分別對應的位置形成複數個透鏡而形成第1微透鏡層的步驟；及在第1微透鏡層的透鏡面上，形成具有比起第1微透鏡層還低折射率的氮氧化矽膜或氧化矽膜而形成第2微透鏡層的步驟。[發明之效果]A method of manufacturing a solid-state imaging device according to one aspect of the present invention includes:A plurality of photoelectric conversion elements are arranged in a matrix in a plan view, and a partition wall is formed at a position surrounded by the photoelectric conversion elements on a semiconductor substrate with an element separation structure between the plurality of photoelectric conversion elements;A step of forming color filters of plural colors at positions corresponding to the photoelectric conversion elements surrounded by the partition wall;On the upper part of the color filter and the partition wall, a silicon nitride film or silicon oxynitride film with a film thickness of 150nm or more and 400nm or less and a refractive index of 1.75 or more and 2.15 or less is formed, and a plurality of them are formed at positions corresponding to the plurality of photoelectric conversion elements. The step of forming a first microlens layer with two lenses; andA step of forming a silicon oxynitride film or a silicon oxide film having a lower refractive index than that of the first microlens layer on the lens surface of the first microlens layer to form the second microlens layer.[Effects of Invention]

依據本發明，可提供一種即便是微細畫素也能使聚光效率提升且所有色為高精細且靈敏度佳的固態攝影元件及固態攝影元件製造方法。According to the present invention, it is possible to provide a solid-state imaging device and a method for manufacturing a solid-state imaging device that can improve the light-collecting efficiency even with fine pixels, and all colors are high-definition and high-sensitivity.

以下，針對本發明的實施形態一邊參照圖面一邊作說明。此處，圖面係示意者，濾色器等之各層的厚度與平面尺寸之關係，各層的厚度之比率等係和現實者相異。又，在表示固態攝影元件的濾色器部之構成的剖面圖中，雖係基於後述的公知之拜耳排列(Bayer arrangement)作記載，但在實際的拜耳排列中，3色以上的濾色器未成為圖面般橫向排列的構造，乃係為了說明而以排列的圖面作記載。以下所示的各實施形態係例示用以將本發明之技術思想具體化的構成，且本發明之技術思想係構成零件的材質、形狀、構造等未特定成如下者。本發明之技術思想係可於申請專利範圍所載的請求項所規定之技術範圍內添加各種變更。Hereinafter, the embodiments of the present invention will be described with reference to the drawings. Here, the drawing is shown schematically, and the relationship between the thickness of each layer of the color filter and the plane size, the ratio of the thickness of each layer, etc. are different from those in reality. In addition, in the cross-sectional view showing the structure of the color filter portion of the solid-state imaging element, although the description is based on the well-known Bayer arrangement described later, in the actual Bayer arrangement, color filters of more than three colors The structure is not arranged horizontally as in the drawing, but is described in the arranged drawing for the purpose of explanation. Each embodiment shown below is an example of a configuration for embodying the technical idea of the present invention, and the technical idea of the present invention is that the materials, shapes, structures, etc. of the constituent parts are not specified as follows. The technical idea of the present invention is that various changes can be added within the technical scope specified in the claims contained in the scope of the patent application.

又本發明中，針對固態攝影元件的光電轉換元件之間有元件分離構造、各濾色器之間有分隔壁構造的構造作了記載，但在對沒有此等構造的公知構造形成微透鏡時也可使用。Furthermore, in the present invention, the solid-state imaging element has an element separation structure between the photoelectric conversion elements and a partition structure between each color filter is described. However, when a microlens is formed for a known structure that does not have such a structure Can also be used.

1.第1實施形態(固態攝影元件的構成)針對本發明第1實施形態的固態攝影元件的構成，使用圖1及圖2作說明。如圖1所示，本實施形態的固態攝影元件1具備半導體基板10、配置在半導體基板10上方的複數個微透鏡200、以及設置在半導體基板10與微透鏡200之間的濾色器100及分隔壁50。又，在微透鏡200之上形成有微透鏡平坦化層300。半導體基板10係具有二維地、亦即平面圖中配置成矩陣狀的複數個光電轉換元件11、及以使在各光電轉換元件11間轉換的電子不會混合之方式設置在光電轉換元件11間的元件分離構造12。1. The first embodiment(Constitution of solid-state imaging device)The structure of the solid-state imaging element according to the first embodiment of the present invention will be described with reference to FIGS. 1 and 2.As shown in FIG. 1, the solid-state imaging element 1 of this embodiment includes asemiconductor substrate 10, a plurality ofmicrolenses 200 arranged above thesemiconductor substrate 10, and acolor filter 100 provided between thesemiconductor substrate 10 and themicrolenses 200 andSeparating wall 50. In addition, a microlensflattening layer 300 is formed on themicrolens 200.Thesemiconductor substrate 10 has a plurality ofphotoelectric conversion elements 11 arranged in a matrix in a two-dimensional manner, that is, in a plan view, and is arranged between thephotoelectric conversion elements 11 so that the electrons converted between the respectivephotoelectric conversion elements 11 are not mixed.的Component separation structure12.

微透鏡200係以複數個微透鏡層所形成。具體言之，微透鏡200係以和光電轉換元件11最接近地設置(亦即，設置在最下部)的第1微透鏡層20、及其上部所形成的第2微透鏡層21所構成。濾色器100係以複數色的濾色器所構成。具體言之，濾色器100係以第1濾色器14、第2濾色器15及第3濾色器16按既定的規則圖案配置所構成。分隔壁50係形成在第1濾色器14、第2濾色器15及第3濾色器16各個之間。分隔壁50係以內側的分隔壁30與將分隔壁30保護地覆蓋的分隔壁31兩層所形成。Themicro lens 200 is formed of a plurality of micro lens layers. Specifically, themicrolens 200 is composed of afirst microlens layer 20 provided closest to the photoelectric conversion element 11 (that is, provided at the lowest portion), and asecond microlens layer 21 formed on the upper portion thereof.Thecolor filter 100 is composed of color filters of plural colors. Specifically, thecolor filter 100 is composed of afirst color filter 14, asecond color filter 15, and athird color filter 16 arranged in a predetermined regular pattern.Thepartition wall 50 is formed between each of thefirst color filter 14, thesecond color filter 15 and thethird color filter 16. Thepartition wall 50 is formed by two layers of thepartition wall 30 on the inner side and thepartition wall 31 protectively covering thepartition wall 30.

圖1雖圖示出在微透鏡200上部存在有微透鏡平坦化層300的構成，但亦可因固態攝影元件1的構成而不存在。又，分隔壁50雖顯示分隔壁30及分隔壁31兩層的構成，但依固態攝影元件1的構成而異，可為1層的構成，亦可為2層以上的構成。又，分隔壁50的高度可低於濾色器100，亦可比其還高。又，固態攝影元件1的畫素尺寸大的情況，也可以沒有分隔壁50。Although FIG. 1 illustrates a configuration in which themicrolens flattening layer 300 is present on the top of themicrolens 200, it may not exist due to the configuration of the solid-state imaging element 1. In addition, although thepartition wall 50 shows a two-layer structure of thepartition wall 30 and thepartition wall 31, it differs depending on the structure of the solid-state imaging element 1, and may have a single-layer structure or a two-layer structure or more. In addition, the height of thepartition wall 50 may be lower than thecolor filter 100, or may be higher. In addition, when the pixel size of the solid-state imaging element 1 is large, thepartition wall 50 may not be provided.

以下，在說明本實施形態的固態攝影元件1時，將在濾色器100的製造步驟上最先形成且在濾色器100中占有面積最廣的濾色器定義成第1濾色器14。又，將在濾色器100的製造步驟上第二個形成的濾色器定義成第2濾色器15、和將在濾色器100的製造步驟上第三個形成的濾色器定義成第3濾色器16。在其他的實施形態亦是相同。又，以下的說明中係假想第1濾色器14是綠色時來作說明，但是第1濾色器14也可以是藍色或紅色。以下，針對固態攝影元件1的各構成要素作詳細說明。Hereinafter, when describing the solid-state imaging element 1 of this embodiment, the color filter that is formed first in the manufacturing steps of thecolor filter 100 and occupies the largest area in thecolor filter 100 is defined as thefirst color filter 14. . In addition, the color filter formed second in the manufacturing step of thecolor filter 100 is defined as thesecond color filter 15, and the color filter formed third in the manufacturing step of thecolor filter 100 is defined as Thethird color filter 16. The same applies to other embodiments. In addition, the following description assumes that thefirst color filter 14 is green, but thefirst color filter 14 may be blue or red.Hereinafter, each component of the solid-state imaging element 1 will be described in detail.

(光電轉換元件及半導體基板)如圖1所示，於依據本實施形態的固態攝影元件1中的半導體基板10，複數個光電轉換元件11與畫素位置對應地呈二維配置。光電轉換元件11的每一者具有將光轉換成電氣信號的機能。又複數個光電轉換元件11的每一者係形成有元件分離構造12，使得光在被光電轉換元件11吸收前進入鄰接的光電轉換元件11或經光電轉換的電子不會流通於鄰接的其他光電轉換元件11的電路。作為元件分離的方法，雖可採用摻雜元件分離區域的半導體基板10、形成空隙或者埋入金屬或氧化物、氮化物、介電體等的方法等各式各樣的構成，但宜為光或電子難以在鄰接的其他光電轉換元件11的電路流動的構造。一般而言，係在藉由蝕刻將光電轉換元件11間的半導體基板10挖掘後，將金屬或氧化物、介電體等堆積而形成。形成有光電轉換元件11的半導體基板10，通常以表面(光射入面)的保護及平坦化為目的而在最表面形成有保護膜。半導體基板10係由能供可見光透射且能耐至少300℃左右的溫度之材料所形成。此處，作為使用於半導體基板10的耐熱材料，例如，可例舉出Si、SiO₂等之氧化物及SiN等之氮化物，以及此等的混合物等之含有Si的材料等。此時，光電轉換元件11係配合後述的微透鏡200的材料、高度等而配置在可受光射入的光之位置。(Photoelectric conversion element and semiconductor substrate) As shown in FIG. 1, in thesemiconductor substrate 10 in the solid-state imaging element 1 according to this embodiment, a plurality ofphotoelectric conversion elements 11 are two-dimensionally arranged corresponding to pixel positions. Each of thephotoelectric conversion elements 11 has a function of converting light into electrical signals. Furthermore, each of the plurality ofphotoelectric conversion elements 11 is formed with anelement separation structure 12 so that light enters the adjacentphotoelectric conversion element 11 before being absorbed by thephotoelectric conversion element 11 or the photoelectrically converted electrons will not circulate through other adjacent photoelectric conversion elements.Conversion element 11 circuit. As the method of element separation, various configurations such as the method of doping thesemiconductor substrate 10 of the element separation region, forming voids, or embedding metals, oxides, nitrides, dielectrics, etc., can be used, but optical Or a structure in which it is difficult for electrons to flow in the circuit of another adjacentphotoelectric conversion element 11. Generally, it is formed by digging thesemiconductor substrate 10 between thephotoelectric conversion elements 11 by etching, and then depositing a metal, oxide, a dielectric, or the like. Thesemiconductor substrate 10 on which thephotoelectric conversion element 11 is formed generally has a protective film formed on the outermost surface for the purpose of protecting and flattening the surface (light incident surface). Thesemiconductor substrate 10 is formed of a material that can transmit visible light and can withstand a temperature of at least about 300°C. Here, as the heat-resistant material used in thesemiconductor substrate 10, for example, include a Si, SiO₂ and other oxides of a nitride such as SiN, and the like as well as mixtures of such Si-containing material and the like. At this time, thephotoelectric conversion element 11 is arranged at a position where light can be received in accordance with the material and height of themicrolens 200 described later.

(濾色器及分隔壁)藉既定的圖案構成濾色器100之第1濾色器14、第2濾色器15及第3濾色器16(第1、第2及第3濾色器的一例)係對射入光進行彩色分離(Color separation)之和各色(綠、藍及紅)對應的濾色器。如圖1所示，第1濾色器14、第2濾色器15及第3濾色器16係設在半導體基板10與微透鏡200之間，且和複數個光電轉換元件11每一者對應的方式以因應於畫素位置而預設的規則圖案配置。(Color filter and partition wall)Thefirst color filter 14, thesecond color filter 15, and the third color filter 16 (an example of the first, second, and third color filters) constituting thecolor filter 100 with a predetermined pattern are for incident light Perform color separation and color filters corresponding to each color (green, blue, and red). As shown in FIG. 1, thefirst color filter 14, thesecond color filter 15, and thethird color filter 16 are provided between thesemiconductor substrate 10 and themicrolens 200, and each of the plurality ofphotoelectric conversion elements 11 The corresponding method is arranged in a regular pattern preset according to the position of the pixel.

圖2係顯示第1濾色器14、第2濾色器15及第3濾色器16及在構成濾色器100的各濾色器之間所形成之分隔壁50的排列之平面圖。圖2所示之排列為所謂的拜耳排列，係鋪滿第1濾色器14、第2濾色器15及第3濾色器16的排列。此外，固態攝影元件1的各濾色器(第1濾色器14、第2濾色器15及第3濾色器16)未必限定拜耳排列，又，各濾色器的顏色亦未受限於紅(R)、綠(G)、藍(B)3色。又，亦可在濾色器100的排列的一部分配置已調整折射率之透明的層或能將可見光遮光且供紅外線透射的層(亦即紅外線用等之濾色器)。又亦可將鄰接的4個畫素設為同色且以16個畫素作拜耳排列之方式使用複數畫素作配置。2 is a plan view showing the arrangement of thefirst color filter 14, thesecond color filter 15, and thethird color filter 16 and thepartition wall 50 formed between the color filters constituting thecolor filter 100. The arrangement shown in FIG. 2 is a so-called Bayer arrangement, which is an arrangement in which thefirst color filter 14, thesecond color filter 15, and thethird color filter 16 are covered. In addition, the color filters of the solid-state imaging element 1 (thefirst color filter 14, thesecond color filter 15, and the third color filter 16) are not necessarily limited to the Bayer arrangement, and the color of each color filter is also not limited. Available in 3 colors of red (R), green (G) and blue (B). In addition, a transparent layer whose refractive index has been adjusted or a layer capable of shielding visible light and transmitting infrared rays (that is, a color filter for infrared rays, etc.) may be arranged in a part of the arrangement of the color filters 100. It is also possible to arrange four adjacent pixels with the same color and 16 pixels in a Bayer arrangement using a plurality of pixels.

構成濾色器100之各濾色器含有既定色的顏料(著色劑)與熱硬化成分或光硬化成分。例如，第1濾色器14係含有作為著色劑的綠色顏料，第2濾色器15係含有藍色顏料，第3濾色器16係含有紅色顏料。Each color filter constituting thecolor filter 100 contains a predetermined color pigment (colorant) and a thermosetting component or a light curing component. For example, thefirst color filter 14 contains a green pigment as a colorant, thesecond color filter 15 contains a blue pigment, and thethird color filter 16 contains a red pigment.

分隔壁50係建構在構成濾色器100之複數色的濾色器(第1濾色器14、第2濾色器15及第3濾色器16)的各自之間。本實施形態中，藉由設於第1濾色器14的側壁部(外周圍)之分隔壁50，可將第1濾色器14、第2濾色器15及第3濾色器16各自分隔。圖1示出分隔壁50作成2層的構成，如圖1所示在內側形成分隔壁30，且分隔壁31形成覆蓋其外側及半導體基板10。Thepartition wall 50 is constructed between each of the color filters (thefirst color filter 14, thesecond color filter 15, and the third color filter 16) constituting the multiple colors of thecolor filter 100. In this embodiment, by thepartition wall 50 provided on the side wall portion (outer periphery) of thefirst color filter 14, thefirst color filter 14, thesecond color filter 15, and thethird color filter 16 can be separated from each other. Separated. FIG. 1 shows a structure in which thepartition wall 50 is formed in two layers. As shown in FIG. 1, thepartition wall 30 is formed on the inner side, and thepartition wall 31 is formed to cover the outer side and thesemiconductor substrate 10.

內側的分隔壁30較佳為以遮光性高且能藉蝕刻等精度佳地微細加工的金屬材料，例如鎢(W)、鋁(Al)、銅(Cu)的膜所形成。又再者，亦可使用下層以鎢形成且上層使用鈦等之複數個金屬膜的積層構造。又亦可不為此等金屬的單體而為使用化合物。Theinner partition wall 30 is preferably formed of a metal material that has high light-shielding properties and can be finely processed by etching or the like, such as a film of tungsten (W), aluminum (Al), and copper (Cu). Furthermore, it is also possible to use a laminated structure in which the lower layer is formed of tungsten and the upper layer is formed of multiple metal films such as titanium. It is also possible to use compounds instead of monomers of such metals.

分隔壁31係覆蓋分隔壁30的外側，且使用SiO₂、SiN、SiON等之氧化物、氮化物等並使用比濾色器低的折射率材料以如光波導管可引導光的構成來形成。又在該分隔壁31成為分隔壁30的保護膜且於分隔壁30使用金屬的情況，可抑制金屬的反應。分隔壁內側的分隔壁30也可使用金屬和氧化物、氮化物等之複數個材料來形成。較佳為以將進入相鄰的濾色器的光遮光、反射且作為光波導管之構成的材料所形成。Thepartition wall 31 covers the outer side of thepartition wall 30, and is formed by using_{oxides, nitrides, etc., such as SiO 2} , SiN, SiON, etc., and using a refractive index material lower than that of a color filter, such as an optical waveguide that can guide light. In addition, when thepartition wall 31 serves as a protective film of thepartition wall 30 and a metal is used for thepartition wall 30, the reaction of the metal can be suppressed. Thepartition wall 30 inside the partition wall can also be formed using multiple materials such as metal, oxide, and nitride. It is preferably formed of a material that shields and reflects light entering the adjacent color filter and serves as the configuration of the optical waveguide.

分隔壁50的高度宜為可獲得所期望的分光特性之各濾色器的膜厚同等者。分隔壁50的高度高於濾色器的情況，後述的微透鏡200的膜厚薄的谷部與分隔壁50之配置在光電轉換元件11的中心部分容易重疊。因此，無法以微透鏡聚光的光從分隔壁50上部射入且通過外側的分隔壁31並在未分光下進入光電轉換元件11的機率上升。另外濾色器100的膜厚在各濾色器間全設為相同膜厚有困難，因此構成為有同等膜厚但具有厚度上的差異。具體言之，宜為從比膜厚最厚的濾色器厚上50nm左右到是膜厚最厚的濾色器的膜厚之一半左右。在依固態攝影元件1的構造而可抑制混色的情況，係即使是濾色器100的膜厚的一半以下的高度也沒有問題。因為在分隔壁50的高度低於濾色器100的情況，由於分隔壁50上部形成有濾色器100，在前述未被分光地從分隔壁50上部射入的光會減低。分隔壁50的橫方向的寬度係在將光遮光、反射且成為光波導管的範圍下越薄越好。因為越薄越能加大光電轉換元件11的開口面積，且能抑制從前述的分隔壁50上部進入的光。具體言之，分隔壁50的寬度宜為100nm以下，更宜為50nm以下。The height of thepartition wall 50 is preferably one that has the same film thickness of each color filter that can obtain the desired spectral characteristics. In the case where the height of thepartition wall 50 is higher than that of the color filter, the thin valley portions of themicrolens 200 described later and the arrangement of thepartition wall 50 are likely to overlap in the central part of thephotoelectric conversion element 11. Therefore, the light that cannot be condensed by the microlens is incident from the upper portion of thepartition wall 50, passes through theouter partition wall 31, and enters thephotoelectric conversion element 11 without being split. In addition, it is difficult for the film thickness of thecolor filter 100 to be the same film thickness among the color filters, so it is configured to have the same film thickness but with a difference in thickness. Specifically, it is preferably from about 50 nm higher than the thickness of the color filter with the thickest film thickness to about half of the film thickness of the color filter with the thickest film thickness.In the case where color mixing can be suppressed depending on the structure of the solid-state imaging element 1, there is no problem even if the height is less than half of the film thickness of thecolor filter 100. In the case where the height of thepartition wall 50 is lower than thecolor filter 100, since thecolor filter 100 is formed on the upper part of thepartition wall 50, the light incident from the upper part of thepartition wall 50 without being separated is reduced. The width of thepartition wall 50 in the lateral direction is as thin as possible in a range that shields and reflects light and serves as an optical waveguide. This is because the thinner it is, the larger the opening area of thephotoelectric conversion element 11 is, and the light entering from the upper part of thepartition wall 50 can be suppressed. Specifically, the width of thepartition wall 50 is preferably 100 nm or less, and more preferably 50 nm or less.

分隔壁50，通常宜為比濾色器100還先形成於半導體基板10。藉由先形成分隔壁50而在格柵上作成有溝的場所形成各濾色器。習知構造的濾色器之形成方法為，在平坦的面上使濾色器具感光性並選擇性曝光顯影而形成矩形的圖案。在進行畫素圖案的微細化之情況，各濾色器的膜厚係成為薄膜的傾向。因此，在以薄膜形成所期望的顏色之情況，具有必須增大顏料等之著色成分的含有量，而感光性成分的含有量變少的結果，圖案化變困難的問題。但是，在既已設置分隔壁50且於其格柵上的溝部填孔以形成各濾色器的情況，只要選擇性曝光的部分夠硬即可。因此，具有上述的圖案化之難易度降低，即使感光性成分的含有量少亦可，濾色器材料的作成難易度變容易的優點。Thepartition wall 50 is generally preferably formed on thesemiconductor substrate 10 before thecolor filter 100. By forming thepartition wall 50 first, each color filter is formed in a grooved place on the grid. The color filter of the conventional structure is formed by making the color filter photosensitive on a flat surface and selectively exposing and developing it to form a rectangular pattern. When the pixel pattern is refined, the film thickness of each color filter tends to become a thin film. Therefore, in the case of forming a desired color with a thin film, it is necessary to increase the content of coloring components such as pigments, and as a result of the decrease in the content of photosensitive components, there is a problem that patterning becomes difficult. However, in the case where thepartition wall 50 is already provided and the grooves on the grid are filled with holes to form each color filter, it is only necessary that the selectively exposed part is hard enough. Therefore, there is an advantage that the ease of patterning described above is reduced, and even if the content of the photosensitive component is small, the ease of preparation of the color filter material becomes easier.

(微透鏡)固態攝影元件1中的微透鏡200，係於半導體基板10上方，配置在與畫素位置對應的位置。亦即，微透鏡200係複數個透鏡分別設置在複數個光電轉換元件11各自對應的位置。微透鏡200係藉由使射入微透鏡200的射入光聚光於光電轉換元件11的每一者上，可彌補光電轉換元件11的靈敏度降低。本發明的微透鏡200係如圖1所示以複數個微透鏡層形成。又，較佳為最接近光電轉換元件11的下層所設置的第1微透鏡層20製作微透鏡形狀，第2微透鏡層21以後的複數個微透鏡層被形成在第1微透鏡層20的透鏡面上的構成。本實施形態中，微透鏡200是以第1微透鏡層20與第2微透鏡層21兩層所形成。(Micro lens)Themicrolens 200 in the solid-state imaging element 1 is above thesemiconductor substrate 10 and is arranged at a position corresponding to the position of the pixel. That is, a plurality of lenses of themicrolens 200 are respectively arranged at positions corresponding to the respectivephotoelectric conversion elements 11. Themicrolens 200 can make up for the decrease in the sensitivity of thephotoelectric conversion element 11 by condensing the incident light that has entered themicrolens 200 on each of thephotoelectric conversion elements 11. Themicrolens 200 of the present invention is formed with a plurality of microlens layers as shown in FIG. 1. Furthermore, it is preferable that thefirst microlens layer 20 provided closest to the lower layer of thephotoelectric conversion element 11 is formed into a microlens shape, and a plurality of microlens layers after thesecond microlens layer 21 are formed on thefirst microlens layer 20 The composition of the lens surface. In this embodiment, themicrolens 200 is formed by two layers of thefirst microlens layer 20 and thesecond microlens layer 21.

為了以微透鏡200使聚光效率提升，第1微透鏡層20較佳為高折射率材料。具體言之較佳為折射率1.75以上2.15以下的範圍。在折射率為2.15以上的材料之情況，微透鏡200的聚光能力雖會提升，但因與濾色器100的折射率差變大使得在微透鏡200與濾色器100之界面等的反射光增加而有聚光效率降低的情況。在微透鏡的習知構造中，一般於微透鏡200使用有機系樹脂的材料，有機系樹脂中即使為高折射率材料亦是1.7以下程度。又，當使用折射率高的有機系材料時，有透射率易降低的傾向。In order to improve the light collection efficiency with themicrolens 200, thefirst microlens layer 20 is preferably made of a high refractive index material. Specifically, the refractive index is preferably in the range of 1.75 or more and 2.15 or less. In the case of a material with a refractive index of 2.15 or higher, although the light-gathering ability of themicrolens 200 will be improved, the difference in refractive index with thecolor filter 100 will increase, causing reflection at the interface between themicrolens 200 and thecolor filter 100. The light increases and the light collection efficiency may decrease. In the conventional structure of the microlens, an organic resin material is generally used for themicrolens 200, and the organic resin is about 1.7 or less even if it is a high refractive index material. In addition, when an organic material with a high refractive index is used, the transmittance tends to decrease easily.

在使用微細的固態攝影元件1之一般的相機模組之情況，微透鏡200之會有光射來的外側係和折射率接近1的空氣接觸。微透鏡200的折射率為1.75以上的情況，基於微透鏡200的聚光能力雖會提升，但因為在微透鏡200與空氣之間的折射率差大，所以變得容易引起光之反射。在該情況，有可能射入微透鏡200內部的光減少，招致受光靈敏度之降低。In the case of a general camera module using a fine solid-state imaging device 1, the outer side of themicrolens 200 from which light is emitted is in contact with air with a refractive index close to 1. When the refractive index of themicrolens 200 is 1.75 or more, although the light-gathering ability of themicrolens 200 is improved, since the refractive index difference between themicrolens 200 and the air is large, it becomes easy to cause light reflection. In this case, the light entering the inside of themicrolens 200 may decrease, resulting in a decrease in light receiving sensitivity.

折射率高且從380nm到700nm的可見光之透射率高的無機材料，可想到氮化矽(折射率：約2.0)、氧化鋯(折射率：約2.2)、氧化鈦(折射率：約2.49)、硫化鋅(折射率：約2.35)、氧化鋅(折射率：約2.01)、氧化鉿(折射率：約1.91)、氮化鋁(折射率：約2.16)、氧化鉭(折射率：約2.16)等。在形成微透鏡200的情況，因為設於下層的濾色器100的耐熱性一般為300℃以下，故較佳為以該溫度以下所形成的材料。形成微透鏡200的材料係能用300℃以下的溫度形成，用乾蝕刻等之公知方法進行形狀加工是容易的，而若是後述的消光係數低的材料的話什麼材料都沒問題，但當考慮因形成溫度或前述的折射率差所致之反射時，較佳為無機材料是使用氮化矽。藉由無機材料是使用透明且呈現高折射率的氮化矽，第1微透鏡層20係成為高折射率的微透鏡。因為第1微透鏡層20呈現高的折射率，即便將第1微透鏡層20的高度形成比習知者還低，亦能使射入光分別射入與各透鏡對應設置的畫素。又，因為第1微透鏡層20的高度可形成比習知還低，所以應射入鄰接的畫素之射入光被第1微透鏡層20所阻斷，可抑制固態攝影元件1整體之受光效率降低。因此，在無損及在各色的靈敏度特性之下，可提供呈現聚光特性的固態攝影元件1。Inorganic materials with high refractive index and high transmittance of visible light from 380nm to 700nm include silicon nitride (refractive index: about 2.0), zirconium oxide (refractive index: about 2.2), and titanium oxide (refractive index: about 2.49) , Zinc sulfide (refractive index: about 2.35), zinc oxide (refractive index: about 2.01), hafnium oxide (refractive index: about 1.91), aluminum nitride (refractive index: about 2.16), tantalum oxide (refractive index: about 2.16) )Wait. In the case of forming themicrolens 200, since the heat resistance of thecolor filter 100 provided in the lower layer is generally 300° C. or lower, a material formed at a temperature or lower is preferable. The material for forming themicrolens 200 can be formed at a temperature of 300°C or less. It is easy to perform shape processing by known methods such as dry etching. However, if it is a material with a low extinction coefficient, which will be described later, there is no problem with any material, but when considering the factors When forming the reflection caused by the temperature or the aforementioned refractive index difference, it is preferable to use silicon nitride as the inorganic material. Since the inorganic material is transparent silicon nitride that exhibits a high refractive index, thefirst microlens layer 20 is a microlens with a high refractive index. Since thefirst microlens layer 20 exhibits a high refractive index, even if the height of thefirst microlens layer 20 is made lower than that of the conventional one, the incident light can be incident on the pixels provided corresponding to each lens. In addition, since the height of thefirst microlens layer 20 can be formed to be lower than that of the conventional one, the incident light that should be incident on the adjacent pixels is blocked by thefirst microlens layer 20, and the overall solid-state imaging element 1 can be suppressed. The light receiving efficiency is reduced. Therefore, it is possible to provide the solid-state imaging element 1 exhibiting light-gathering characteristics without compromising the sensitivity characteristics of each color.

氮化矽(Si₃N₄)的折射率為2.0左右，但矽與氮之比例依成膜條件而變化，折射率係從1.7變化到2.1左右。又，在將氮化矽用作微透鏡200的材料之情況必須透射率為高者。透射率係依材質的膜厚而變化，故而在指標方面能以光學常數的消光係數來表示。發明者們的知識見解為消光係數在使用於微透鏡的材料上是重要的。折射率與消光係數呈現因成膜條件而異。在固態攝影元件1所使用的氮化矽多為使用CVD(Chemical Vapor Deposition)所形成。使用CVD形成時的成膜條件之品質依溫度、壓力、氣體種類及氣體流量等之控制而異。以下層的濾色器100之耐熱溫度300℃以下形成的情況，藉由在上述條件下使用電漿源且使用在低壓環境下能採用低溫工序的電漿CVD(電漿增強化學氣相沉積；Plasma-enhanced Chemical Vapor Deposition)，容易形成品質良好的氮化矽。在氮化矽的折射率高的成膜條件下消光係數易變不佳，折射率與消光係數雙方優異的成膜條件的情況係條件的範圍狹窄，膜所內含的應力易變高。應力高的情況，有不適合於在濾色器100上形成微透鏡200時的傾向。因此，作為適合於微透鏡200的氮化矽膜，較佳為折射率為1.75以上2.0以下且在380nm以上700nm以下的可見光之範圍下的消光係數為1.0×10^-3以下。再者，作為適合於微透鏡200的氮化矽膜，最好為折射率為1.85以上2.0以下且在波長300nm以上700nm以下的範圍的消光係數為1.0×10^-3以下的膜質。The refractive index of silicon nitride (Si₃ N₄ ) is about 2.0, but the ratio of silicon to nitrogen varies depending on the film forming conditions, and the refractive index varies from 1.7 to about 2.1. In addition, when silicon nitride is used as the material of themicrolens 200, the transmittance must be high. The transmittance varies depending on the film thickness of the material, so it can be expressed by the extinction coefficient of the optical constant in terms of index. The knowledge of the inventors is that the extinction coefficient is important in the material used for the microlens. The refractive index and extinction coefficient are different depending on the film forming conditions. The silicon nitride used in the solid-state imaging element 1 is mostly formed by CVD (Chemical Vapor Deposition). The quality of the film forming conditions when formed by CVD varies depending on the control of temperature, pressure, gas type, and gas flow rate. When the heat-resistant temperature of thecolor filter 100 in the lower layer is formed below 300°C, by using a plasma source under the above conditions and using a plasma CVD (plasma-enhanced chemical vapor deposition) that can adopt a low-temperature process in a low-pressure environment; Plasma-enhanced Chemical Vapor Deposition), easy to form good quality silicon nitride. The extinction coefficient tends to be poor under the film forming conditions where the refractive index of silicon nitride is high, and the film forming conditions with both the refractive index and the extinction coefficient are excellent because the range of conditions is narrow, and the stress contained in the film tends to become high. When the stress is high, there is a tendency that it is not suitable for forming themicrolens 200 on thecolor filter 100. Therefore, as a silicon nitride film suitable for themicrolens 200, it is preferable that the refractive index is 1.75 or more and 2.0 or less, and the extinction coefficient in the visible light range of 380 nm or more and 700 nm or less is 1.0×10⁻³ or less. In addition, as a silicon nitride film suitable for themicrolens 200, it is preferable to have a refractive index of 1.85 or more and 2.0 or less, and an extinction coefficient of 1.0×10^-3 or less in the range ofwavelength 300 nm or more and 700 nm or less.

前述的條件雖是形成氮化矽膜的情況，但藉由在用電漿CVD形成時併用含氧的N₂O氣體等，可形成氮氧化矽(組成式SiON)膜。氮氧化矽膜係藉由氧的含有量可形成從氮化矽(折射率：2.0)到氧化矽(折射率：1.45)的折射率，消光係數也容易控制。因此，亦可將氮氧化矽使用於第1微透鏡層20。Although the aforementioned conditions are for the formation of a silicon nitride film, a silicon oxynitride (compositional SiON) film can be formed_{by using an oxygen-containing N 2 O gas or the like in the formation by plasma CVD.} The silicon oxynitride film can form a refractive index from silicon nitride (refractive index: 2.0) to silicon oxide (refractive index: 1.45) due to the oxygen content, and the extinction coefficient is also easy to control. Therefore, silicon oxynitride can also be used for thefirst microlens layer 20.

作為第1微透鏡層20的形成方法，在濾色器100上以各種成膜條件形成高折射的第1層。作為第1層，較佳為以電漿CVD形成前述的氮化矽層的方法。其次，形成用以形成後述的透鏡基質之屬於第2層的中間犧牲層。中間犧牲層係利用樹脂材料所形成，使用例如未具有熱流性的感光性樹脂。藉此，可回避因熱流使感光性樹脂圖案熔融，體積膨脹造成鄰接的透鏡彼此接觸的情形。其結果，可防止在相鄰的透鏡彼此的交界部分發生形狀崩塌的情形。此處，在形成透鏡基質方面，可採用的不因熱而流動的感光性樹脂，以玻璃轉移溫度高、且依100～220℃的條件之熱處理在硬化前形狀不崩塌的熱塑性之樹脂材料是適合的。作為此種不因熱而流動感光性樹脂，較佳為含有質量平均分子量(Mw：依據凝膠滲透層析術(gel permeation chromatography；GPC)的苯乙烯轉化的測定値)為10,000以上30,000以下的基底樹脂。更佳為，質量平均分子量為20,000以上30,000以下。藉由基底樹脂的質量平均分子量為10,000以上而提升耐熱性、耐熱流性。又，藉由基底樹脂的質量平均分子量設為30,000以下，因顯影時的溶解性不會降低，所以可抑制殘渣之產生。As a method of forming thefirst microlens layer 20, a highly refractive first layer is formed on thecolor filter 100 under various film forming conditions. As the first layer, a method of forming the aforementioned silicon nitride layer by plasma CVD is preferable. Next, an intermediate sacrificial layer belonging to the second layer for forming the lens substrate described later is formed. The intermediate sacrificial layer is formed of a resin material, and for example, a photosensitive resin having no thermal fluidity is used. By this, it is possible to avoid the situation where the photosensitive resin pattern is melted by the heat flow, and the volume expansion causes the adjacent lenses to contact each other. As a result, it is possible to prevent the occurrence of shape collapse at the boundary portion between adjacent lenses.Here, in forming the lens matrix, a photosensitive resin that does not flow due to heat can be used, and a thermoplastic resin material that has a high glass transition temperature and heat treatment under the conditions of 100 to 220°C that does not collapse before curing is suitable. As such a photosensitive resin that does not flow due to heat, it is preferable to contain a mass average molecular weight (Mw: measured value of styrene conversion based on gel permeation chromatography (GPC)) of 10,000 or more and 30,000 or less. Base resin. More preferably, the mass average molecular weight is 20,000 or more and 30,000 or less. The base resin has a mass average molecular weight of 10,000 or more to improve heat resistance and hot flow resistance. In addition, by setting the mass average molecular weight of the base resin to 30,000 or less, the solubility during development does not decrease, so the generation of residues can be suppressed.

接著，為了形成透鏡基質而將具有感光性的光阻劑形成於中間犧牲層上。藉由將該光阻劑選擇性地曝光顯影而在將形成微透鏡的場所形成光阻劑，再以該光阻劑的形狀會崩塌的溫度條件進行加熱烘烤，使阻劑形狀因熱流動形成透鏡形狀的阻劑。其次，以透鏡形狀的阻劑為遮罩對中間犧牲層全面進行乾蝕刻，藉由以正型的阻劑全部的量消失的時間設定進行蝕刻，形成在中間犧牲層轉印了透鏡形狀的透鏡基質。接著，以透鏡基質為遮罩對第1層全面進行乾蝕刻，在第1層轉印透鏡基質的形狀而形成第1微透鏡層20。微透鏡的透鏡形成方法除了使用前述之阻劑的熱流法之方法外也能使用公知的方法。例如，以使用灰階圖案的光罩，藉由調整曝光量，於顯影後直接成為透鏡形狀之方式形成亦可。因為在使用任一種方法都難以將第1微透鏡層20直接形成透鏡形狀，所以適合的方法為，在形成平坦的第1微透鏡層20上使用在之後會被除去的犧牲層製作出透鏡形狀，再將其形狀藉由公知的蝕刻方法轉印到第1微透鏡層20。Next, in order to form a lens matrix, a photosensitive photoresist is formed on the intermediate sacrificial layer. By selectively exposing and developing the photoresist, the photoresist is formed in the place where the microlenses will be formed, and then the photoresist is heated and baked at a temperature condition where the shape of the photoresist will collapse, so that the shape of the resist flows due to heat Form a resist in the shape of a lens. Next, dry etching is performed on the entire surface of the intermediate sacrificial layer with a lens-shaped resist as a mask, and etching is performed with the time setting when the entire amount of the positive type resist disappears, and a lens with the lens shape transferred to the intermediate sacrificial layer is formed. Matrix. Next, the entire surface of the first layer is dry-etched using the lens substrate as a mask, and the shape of the lens substrate is transferred to the first layer to form thefirst microlens layer 20.The lens forming method of the microlens can also use a known method in addition to the heat flow method using the aforementioned resist. For example, it is also possible to form a photomask using a grayscale pattern to form a lens shape directly after development by adjusting the exposure amount. Because it is difficult to directly form thefirst microlens layer 20 into a lens shape using either method, a suitable method is to use a sacrificial layer that will be removed later to create a lens shape on the flatfirst microlens layer 20 Then, the shape is transferred to thefirst microlens layer 20 by a known etching method.

此時，第1微透鏡層20的高度方向的膜厚為150nm以上400nm以下。此外，「第1微透鏡層20的高度方向的膜厚」，意指從半圓形狀透鏡的底面(第1實施形態中的濾色器100的上面)到第1微透鏡層20的透鏡頂點為止的高度。在各光電轉換元件11的間距(亦即第1微透鏡層20所具有的複數個透鏡之間距)為1.0μm以下的微細構造之情況，第1微透鏡層20的高度方向的膜厚只要為膜厚150nm以上400nm即可，更佳為150nm以上300nm。在微細的畫素圖案中，當將第1微透鏡層20的高度方向的膜厚設大時，應射入鄰接的畫素之射入光被第1微透鏡層20阻斷，具有固態攝影元件1的受光效率(受光靈敏度；Responsivity)降低的問題。又，當在微透鏡200形成部位的面積狹窄的條件下將第1微透鏡層20的膜厚(透鏡高度)設厚時，與透鏡的谷部對應之部分的膜厚變厚，亦有透鏡形狀崩塌導致形成光混色的區域之問題。然而，藉由將膜厚範圍設為上述範圍，可抑制此等問題，可提供呈現高聚光特性的固態攝影元件1。又，因為藉由將第1微透鏡層20的高度設低可將聚光點的位置置於濾色器100，所以靈敏度特性變好。特別是，藉由將第1微透鏡層20的高度設為150nm以上300nm以下的範圍，可在綠(G)、藍(B)、紅(R)的所有色中獲得良好的靈敏度特性。At this time, the film thickness in the height direction of thefirst microlens layer 20 is 150 nm or more and 400 nm or less. In addition, "the film thickness in the height direction of thefirst microlens layer 20" means from the bottom surface of the semicircular lens (the upper surface of thecolor filter 100 in the first embodiment) to the lens vertex of thefirst microlens layer 20 the height of. In the case of a fine structure in which the pitch of each photoelectric conversion element 11 (that is, the pitch between the plurality of lenses of the first microlens layer 20) is 1.0 μm or less, the film thickness in the height direction of thefirst microlens layer 20 may be The film thickness may be 150 nm or more and 400 nm, more preferably 150 nm or more and 300 nm.In the fine pixel pattern, when the thickness of thefirst microlens layer 20 in the height direction is set to be large, the incident light that should enter the adjacent pixels is blocked by thefirst microlens layer 20, and solid-state photography is possible. The light-receiving efficiency (Responsivity) of theelement 1 is reduced. In addition, when the film thickness (lens height) of thefirst microlens layer 20 is made thick under the condition that the area where themicrolens 200 is formed is narrow, the film thickness of the portion corresponding to the valley of the lens becomes thicker, and there is also a lens The collapse of the shape leads to the problem of the formation of light-mixed areas. However, by setting the film thickness range to the above-mentioned range, these problems can be suppressed, and the solid-state imaging device 1 exhibiting high light-gathering characteristics can be provided. In addition, by lowering the height of thefirst microlens layer 20, the position of the condensing point can be placed on thecolor filter 100, so that the sensitivity characteristics are improved. In particular, by setting the height of thefirst microlens layer 20 in the range of 150 nm or more and 300 nm or less, good sensitivity characteristics can be obtained in all colors of green (G), blue (B), and red (R).

微透鏡200的第2微透鏡層21係減低基於第1微透鏡層20的反射之層。如同前述，在第1微透鏡層20的折射率為1.75以上2.15以下程度的情況，因為折射率低的空氣處於外側，故在第1微透鏡層20表面之反射多，易引起靈敏度降低。因此，在以複數個層所構成的微透鏡200的第2以後的層，係控制折射率並形成為防反射層。亦即，藉由在第1微透鏡層20的透鏡面上設置第2微透鏡層21，可防止損及固態攝影元件1的靈敏度特性。因此，第2微透鏡層21的折射率較佳為比第1微透鏡層20的折射率還低，較佳為例如1.4以上1.75以下。在使用折射率為1.75以上的材料之情況，在第1微透鏡層20的透鏡表面(第1微透鏡層20與第2微透鏡層21之交界)之射入光的反射多，在固態攝影元件1易引起靈敏度降低。特別是，畫素一經微細化就容易發現上述的反射光。因此，藉由將第2微透鏡層21的折射率設為1.4以上1.75以下，可提供能抑制反射光之微細的固態攝影元件1。本實施例中，微透鏡200係示出以2層構成的情況，作為第2微透鏡層21，氧化矽(SiO₂)或氧量多的氮氧化矽(SiON)是適合的。亦即，第2微透鏡層21較佳為氧含有量比第1微透鏡層20還高。使用氧化矽的情況，除了電漿CVD等之氣相成膜方法以外，亦可使用SOG(Spin On Glass；旋轉塗布玻璃)或矽氧烷等之塗布型的材料來形成。只要為能以位在前述下層的濾色器之耐熱溫度300℃以下形成的方法，則亦可使用公知的任何方法。Thesecond microlens layer 21 of themicrolens 200 is a layer that reduces the reflection by thefirst microlens layer 20. As described above, when the refractive index of thefirst microlens layer 20 is about 1.75 or more and 2.15 or less, since air with a low refractive index is on the outside, there is much reflection on the surface of thefirst microlens layer 20, which tends to cause a decrease in sensitivity. Therefore, the second and subsequent layers of themicrolens 200 composed of a plurality of layers are formed as an anti-reflection layer by controlling the refractive index. That is, by providing thesecond microlens layer 21 on the lens surface of thefirst microlens layer 20, it is possible to prevent the sensitivity characteristics of the solid-state imaging device 1 from being impaired. Therefore, the refractive index of thesecond microlens layer 21 is preferably lower than the refractive index of thefirst microlens layer 20, and is preferably 1.4 or more and 1.75 or less, for example. In the case of using a material with a refractive index of 1.75 or more, the incident light on the lens surface of the first microlens layer 20 (the boundary between thefirst microlens layer 20 and the second microlens layer 21) is more reflected.Element 1 is liable to cause sensitivity reduction. In particular, once the pixels are miniaturized, the above-mentioned reflected light can be easily found. Therefore, by setting the refractive index of thesecond microlens layer 21 to be 1.4 or more and 1.75 or less, it is possible to provide a fine solid-state imaging device 1 capable of suppressing reflected light. In this embodiment, themicrolens 200 is composed of two layers. As thesecond microlens layer 21, silicon_{oxide (SiO 2} ) or silicon oxynitride (SiON) with a large amount of oxygen is suitable. In other words, thesecond microlens layer 21 preferably has a higher oxygen content than thefirst microlens layer 20. In the case of using silicon oxide, in addition to vapor phase film formation methods such as plasma CVD, SOG (Spin On Glass) or silicone or other coating-type materials can also be used for formation. As long as it is a method that can be formed with the heat-resistant temperature of the color filter in the lower layer of 300°C or lower, any known method can also be used.

第2微透鏡層21的膜厚若可形成薄，則適合較薄者。具體言之，第2微透鏡層21的膜厚較佳為5nm以上2000nm以下，更佳為10nm以上200nm以下，再更佳為50nm以上150nm以下。又，第2微透鏡層21的膜厚T2對上述的第1微透鏡層20的膜厚T1之比率(T2/T1)較佳為0.125以上1.0以下。If the film thickness of thesecond microlens layer 21 can be made thin, it is suitable for a thinner one. Specifically, the film thickness of thesecond microlens layer 21 is preferably 5 nm or more and 2000 nm or less, more preferably 10 nm or more and 200 nm or less, and still more preferably 50 nm or more and 150 nm or less.In addition, the ratio (T2/T1) of the film thickness T2 of thesecond microlens layer 21 to the film thickness T1 of the above-mentionedfirst microlens layer 20 is preferably 0.125 or more and 1.0 or less.

(微透鏡平坦化層)本實施形態中，示出於微透鏡200在上部(光射入方向)，形成有設於微透鏡200的透鏡面上且上面形成平坦的微透鏡平坦化層300之構造。一般的固態攝影元件之情況，微透鏡200的外側為空氣層，作為相機模組構造，在其上部形成聚光透鏡或紅外線截止板等之模組構造。在本實施形態所示那種一個畫素尺寸成為1μm以下那樣的已微細化的固態攝影元件1之情況，微透鏡200的構造亦同樣地被微細化，成為構成微透鏡200之各透鏡的間隔成為接近於光的波長之構成。因此，微透鏡的構造自體很可能如菲涅耳透鏡或繞射透鏡般成為對射入的光帶來影響之構造。因此，即便是如前者所示空氣層在平時是位在外側那種一般的固態攝影元件之情況，在微透鏡200上部形成微透鏡平坦化層300是適合的。(Micro lens flattening layer)In this embodiment, themicrolens 200 has a structure in which a flatmicrolens flattening layer 300 is formed on the lens surface of themicrolens 200 on the upper part (in the light incident direction). In the case of a general solid-state imaging device, the outer side of themicrolens 200 is an air layer, which serves as a camera module structure, and a module structure such as a condenser lens or an infrared cutoff plate is formed on the upper part of themicrolens 200.In the case of the miniaturized solid-state imaging element 1 whose pixel size is 1 μm or less as shown in this embodiment, the structure of themicrolens 200 is similarly miniaturized, and the distance between each lens constituting themicrolens 200 It becomes a structure close to the wavelength of light. Therefore, the structure itself of the microlens is likely to be a structure that affects the incident light like a Fresnel lens or a diffractive lens. Therefore, even in the case of a general solid-state imaging element where the air layer is usually located outside as shown in the former, it is suitable to form themicrolens flattening layer 300 on themicrolens 200.

作為微透鏡平坦化層300的材料，可想到有機材料或無機材料，宜為經考慮折射率的材料。在微透鏡200的上方為空氣那樣的一般模組之情況，宜為在空氣與作為微透鏡200的表面的第2微透鏡層21的折射率之間的材料。具體言之較佳為折射率1.1以上1.6以下程度的折射率，更佳為1.20以上1.45以下。宜為是該範圍的折射率且為相對於可見光是透射率高的材料。藉此，抑制經由微透鏡平坦化層300射入的光在微透鏡200表面反射的情況，可提升聚光特性、靈敏度特性並獲得微細的固態攝影元件。又，膜厚雖然100nm以上100μm以下程度沒有特別限制，但宜為可將微透鏡200平坦化的膜厚。作為低折射率材料，透過在有機系樹脂含有矽氧烷系聚合物、二氧化矽、氟聚合物等作為無機聚合物，或透過使之含有中空填料，可形成折射率1.6以下。不受上述的方法所限，只要是透明性高且能作成平坦的材料之組合就沒有問題。As the material of themicrolens flattening layer 300, an organic material or an inorganic material can be conceived, and a material having a refractive index in consideration is preferable. In the case of a general module such as air above themicrolens 200, it is preferably a material between air and the refractive index of thesecond microlens layer 21 as the surface of themicrolens 200. Specifically, the refractive index is preferably 1.1 or more and 1.6 or less, and more preferably 1.20 or more and 1.45 or less. It is preferably a material with a refractive index in this range and a high transmittance with respect to visible light. Thereby, the light incident through themicrolens flattening layer 300 is suppressed from being reflected on the surface of themicrolens 200, and the light collection characteristics and sensitivity characteristics can be improved, and a fine solid-state imaging element can be obtained. In addition, although the film thickness is not particularly limited to 100 nm or more and 100 μm or less, it is preferably a film thickness that can flatten themicrolens 200. As a low-refractive index material, the organic resin contains silicone-based polymers, silicon dioxide, fluoropolymers, etc. as inorganic polymers, or through the inclusion of hollow fillers, to form a refractive index of 1.6 or less. It is not limited by the above-mentioned method, as long as it is a combination of high transparency and flat materials, there is no problem.

＜第1實施形態的效果＞本實施形態中，在濾色器100之上形成有微透鏡200。微透鏡200係於第1微透鏡層20之上形成有第2微透鏡層21。第1微透鏡層20的膜厚(從透鏡底面到透鏡頂點為止的高度)係150nm以上400nm以下。藉由此等構成，藉由折射率高的微透鏡使聚光能力高，藉由從複數個層形成的微透鏡200可減低在微透鏡部分之反射。又藉由設定第1微透鏡層20的高度，可利用所有濾色器形成高靈敏度。<Effects of the first embodiment>In this embodiment, amicro lens 200 is formed on thecolor filter 100. Themicrolens 200 is formed with asecond microlens layer 21 on thefirst microlens layer 20. The film thickness (height from the bottom surface of the lens to the apex of the lens) of thefirst microlens layer 20 is 150 nm or more and 400 nm or less. With this configuration, the light-gathering ability is high by the microlens with high refractive index, and the reflection at the microlens part can be reduced by themicrolens 200 formed from a plurality of layers. Furthermore, by setting the height of thefirst microlens layer 20, all the color filters can be used to form high sensitivity.

本實施形態中，僅基於一般的光電轉換元件之構成作描述，近年來，亦有為了焦點檢測而改變光電轉換元件部的一部分構造以形成像面相位差對焦(Phase Detection AF)的構造。使用攝像元件內的複數個焦點檢測畫素從信號求得偏移量，算出焦點的修正量。在那樣構造的情況，有時在攝像元件內改變一部分排列或將複數個畫素以一個畫素形成。像面相位差對焦的畫素有1畫素份、2畫素份、4畫素份等之各式各樣的構成，但在該情況，和光電轉換元件對應的濾色器或微透鏡未必與光電轉換元件成為一對。例如，相對於光電轉換元件為複數時，濾色器及微透鏡為1個，或相對於光電轉換元件與濾色器為複數時，微透鏡為1個的構成。又，配合此等的構成而形成分隔壁50。即便是形成有此種像面相位差對焦的固態攝影元件之情況，本實施形態亦可適用，該部分的微透鏡和光電轉換元件未必成為一對，僅形狀稍不同，這以外的部分和實施形態相同。In this embodiment, the description is based only on the structure of a general photoelectric conversion element. In recent years, there has also been a structure in which a part of the photoelectric conversion element portion is changed for focus detection to form phase detection AF (Phase Detection AF). A plurality of focus detection pixels in the imaging element are used to obtain the offset amount from the signal, and calculate the focus correction amount. In the case of such a structure, a part of the arrangement in the imaging element is changed or a plurality of pixels are formed by one pixel. The image plane phase difference focusing pixels have various configurations such as 1-pixel, 2-pixel, 4-pixel, etc. However, in this case, the color filter or microlens corresponding to the photoelectric conversion element is not necessarily It becomes a pair with the photoelectric conversion element. For example, when the photoelectric conversion element is plural, the color filter and the microlens are one, or when the photoelectric conversion element and the color filter are plural, the microlens is one configuration. In addition, thepartition wall 50 is formed in accordance with these structures. Even in the case of a solid-state imaging element with such image-plane phase difference focusing, this embodiment is also applicable. The microlens and the photoelectric conversion element in this part may not necessarily be a pair, and only the shape is slightly different. The other parts and implementation The shape is the same.

2.第2實施形態其次，針對本發明第2實施形態，使用圖3作說明。如圖3所示，本實施形態的固態攝影元件2與第1實施形態的固態攝影元件1的不同點為，在濾色器100與微透鏡200之間形成濾色器平坦化層40，以將濾色器100的凹凸平坦化並緩和微透鏡200形成時之應力。2. The second embodimentNext, the second embodiment of the present invention will be described with reference to FIG. 3. As shown in FIG. 3, the solid-state imaging element 2 of this embodiment differs from the solid-state imaging element 1 of the first embodiment in that a colorfilter flattening layer 40 is formed between thecolor filter 100 and themicrolens 200 to The unevenness of thecolor filter 100 is flattened and the stress when themicrolens 200 is formed is alleviated.

以下，針對固態攝影元件2的構成，記載和第1實施形態中的固態攝影元件1的製造方法不同的部分。Hereinafter, regarding the configuration of the solid-state imaging element 2, the differences from the manufacturing method of the solid-state imaging element 1 in the first embodiment will be described.

(濾色器平坦化層)濾色器平坦化層40被形成在半導體基板10上所形成的濾色器100及分隔壁50的上面。濾色器平坦化層40的膜厚係形成可將由形成濾色器100的各濾色器(第1濾色器14、第2濾色器15、第3濾色器16)與分隔壁50所形成的階差平坦化的膜厚。又，在濾色器平坦化層40的上部形成第1微透鏡層20，但以無機材料形成第1微透鏡層20，形成折射率高且消光係數低的微透鏡之情況，帶有應力地形成微透鏡的可能性容易變高。在微透鏡200所內含的應力大的情況，於烘烤步驟等之後加熱步驟已進行時，有時會因為下層的濾色器100與微透鏡200的熱膨脹係數不同而發生裂紋、透鏡與濾色器位置偏移等之問題。濾色器平坦化層40可緩和此種應力的偏移。又，在形成第1微透鏡層20時，以重視折射率或消光係數的條件下成膜的情況，有時平坦性差而順應圖案的凹凸被成膜，有在與濾色器100之間產生間隙的情況。然而，因在第1微透鏡層20下層形成濾色器平坦化層40，掩埋濾色器平坦化層40與濾色器100之間的間隙，可防止靈敏度特性之劣化。(Color filter flattening layer)The colorfilter planarization layer 40 is formed on thecolor filter 100 and thepartition wall 50 formed on thesemiconductor substrate 10. The film thickness of the colorfilter flattening layer 40 can be formed by the color filters (thefirst color filter 14, thesecond color filter 15, the third color filter 16) forming thecolor filter 100 and thepartition wall 50 The thickness of the formed step flattened film. In addition, thefirst microlens layer 20 is formed on the upper part of the colorfilter flattening layer 40, but thefirst microlens layer 20 is formed of an inorganic material to form microlenses with a high refractive index and a low extinction coefficient. The possibility of forming microlenses tends to increase. When the stress contained in themicrolens 200 is large, when the heating step is performed after the baking step, etc., cracks may occur due to the difference in the thermal expansion coefficients of thecolor filter 100 and themicrolens 200 in the lower layer. The position of the color device is offset and so on. The colorfilter flattening layer 40 can alleviate the shift of such stress. In addition, when forming thefirst microlens layer 20 under the condition of focusing on the refractive index or extinction coefficient, the flatness may be poor and the unevenness conforming to the pattern may be formed, which may occur between thecolor filter 100 and thecolor filter 100. The gap situation. However, since the colorfilter flattening layer 40 is formed under thefirst microlens layer 20, the gap between the colorfilter flattening layer 40 and thecolor filter 100 is buried, so that the sensitivity characteristics can be prevented from deteriorating.

本實施形態中，微透鏡200的折射率為1.75以上2.15以下，各濾色器的折射率雖按各色而異，一般為1.4以上1.7以下程度。因此，當濾色器100與微透鏡200之間形成有折射率大不相同的材料時，在界面容易引起反射，有可能發生靈敏度降低。因此，濾色器平坦化層40的折射率較佳為1.6以上1.8以下，更佳為1.6以上1.7以下。在濾色器平坦化層40的折射率為1.6以上1.8以下的情況，可縮小與第1微透鏡層20的折射率之差使聚光特性提升。又，構成濾色器平坦化層40之材料係難以被施加來自有機樹脂等之應力的材料，較佳為相對於波長380nm以上700nm以下的可見光呈透明且透射率高的材料。In this embodiment, the refractive index of themicrolens 200 is 1.75 or more and 2.15 or less. Although the refractive index of each color filter differs for each color, it is generally 1.4 or more and 1.7 or less. Therefore, when a material with a significantly different refractive index is formed between thecolor filter 100 and themicrolens 200, reflection is likely to occur at the interface, and sensitivity reduction may occur. Therefore, the refractive index of the colorfilter flattening layer 40 is preferably 1.6 or more and 1.8 or less, and more preferably 1.6 or more and 1.7 or less. When the refractive index of the colorfilter flattening layer 40 is 1.6 or more and 1.8 or less, it is possible to reduce the difference in refractive index from thefirst microlens layer 20 and improve the light-gathering characteristics.In addition, the material constituting the colorfilter flattening layer 40 is a material that is difficult to be subjected to stress from an organic resin or the like, and is preferably a material that is transparent and has high transmittance to visible light having a wavelength of 380 nm or more and 700 nm or less.

作為濾色器平坦化層40的材料，藉由含有例如丙烯酸系樹脂、環氧系樹脂、聚醯亞胺系樹脂、酚醛清漆系樹脂、聚酯系樹脂、胺基甲酸酯系樹脂、三聚氰胺系樹脂、尿素系樹脂、苯乙烯系樹脂及矽系樹脂等中的一或複數樹脂所形成。又濾色器平坦化層40，除了有機化合物以外，亦能以含有例如矽、碳、氧、氫、錫、鋅、銦、鋁、鎵、鈦、鉬、鎢、鈮、鉭、鉿、銀及氟之中至少1種的化合物、氧化化合物或氮化化合物所形成。作為此等材料的化合物，可使用例如ITO或ZnO、TiO₂、HfO₂等。又，濾色器平坦化層40係藉由此等材料形成單層或多層。本實施形態中，亦能藉由在濾色器平坦化層40使用有機系樹脂來形成。又作為濾色器平坦化層40的材料，亦能藉由以氮氧化矽增加氧的比例而形成，調整折射率形成為平坦化層。As the material of the colorfilter flattening layer 40, by containing, for example, acrylic resin, epoxy resin, polyimide resin, novolac resin, polyester resin, urethane resin, melamine It is formed of one or more resins among the resin, urea resin, styrene resin, and silicon resin. Furthermore, the colorfilter planarization layer 40, in addition to organic compounds, can also contain, for example, silicon, carbon, oxygen, hydrogen, tin, zinc, indium, aluminum, gallium, titanium, molybdenum, tungsten, niobium, tantalum, hafnium, and silver. And at least one compound among fluorine, an oxidizing compound, or a nitride compound. As a compound of these materials, for example, ITO or ZnO, TiO₂ , HfO₂ and the like can be used. In addition, the colorfilter planarization layer 40 is formed into a single layer or multiple layers by such materials. In this embodiment, it can also be formed by using an organic resin for the colorfilter flattening layer 40. As the material of the colorfilter flattening layer 40, it can also be formed by increasing the proportion of oxygen with silicon oxynitride, and adjusting the refractive index to form the flattening layer.

濾色器平坦化層40的膜厚較佳為10nm以上300nm以下之範圍的膜厚。又，從固態攝影元件2的微細化及抑制混色的觀點，較佳為濾色器平坦化層40較薄者，更佳為濾色器平坦化層40的膜厚為10nm以上150nm以下。又，本實施形態的濾色器平坦化層40亦有緩和應力或熱膨脹係數之差的目的，在達成該目的之範圍較佳為薄膜。The film thickness of the colorfilter planarization layer 40 is preferably a film thickness in the range of 10 nm or more and 300 nm or less. Furthermore, from the viewpoint of miniaturization of the solid-state imaging element 2 and suppression of color mixing, it is preferable that the colorfilter flattening layer 40 is thinner, and it is more preferable that the thickness of the colorfilter flattening layer 40 is 10 nm or more and 150 nm or less. In addition, the colorfilter flattening layer 40 of the present embodiment also has the purpose of alleviating the stress or the difference in the coefficient of thermal expansion, and a thin film is preferable to achieve this purpose.

在將上述那樣形成的濾色器100平坦化的濾色器平坦化層40上形成有第1微透鏡層20。將第1微透鏡層20以無機材料形成的情況，就提高折射率且使消光係數接近0的條件而言，容易內含應力。和第1實施形態同樣地，在第1微透鏡層20使用氮化矽(SiN)的情況，該傾向變得顯著。第1實施形態中，因為要在下層的濾色器100上直接形成第1微透鏡層20，所以必須減低應力來形成，可採取的形成條件之範圍有變窄的傾向。本實施形態中，因為在第1微透鏡層20下層設置濾色器平坦化層40，所以具有擴大第1微透鏡的形成條件的範圍之優點。Thefirst microlens layer 20 is formed on the colorfilter flattening layer 40 that flattens thecolor filter 100 formed as described above. In the case where thefirst microlens layer 20 is formed of an inorganic material, the conditions for increasing the refractive index and making the extinction coefficient close to zero tend to include stress. As in the first embodiment, when silicon nitride (SiN) is used for thefirst microlens layer 20, this tendency becomes remarkable. In the first embodiment, since thefirst microlens layer 20 is to be formed directly on thelower color filter 100, it is necessary to reduce the stress to form it, and the range of possible formation conditions tends to be narrowed. In this embodiment, since the colorfilter flattening layer 40 is provided under thefirst microlens layer 20, there is an advantage of expanding the range of the first microlens formation conditions.

本實施形態中，第1微透鏡層20的高度(從濾色器平坦化層40上面到第1微透鏡層20頂點為止的高度)較佳為150nm到400nm程度。In this embodiment, the height of the first microlens layer 20 (the height from the upper surface of the colorfilter flattening layer 40 to the apex of the first microlens layer 20) is preferably about 150 nm to 400 nm.

＜變形例＞以下，針對本發明第2實施形態的變形例，使用圖4作說明。如圖3所示，本實施形態的固態攝影元件2雖具有微透鏡平坦化層300，但未受限於此種構成。例如，如圖4所示，第2實施形態的變形例之固態攝影元件2A具備半導體基板10、濾色器100、濾色器平坦化層40、微透鏡200、及分隔壁50。亦即，在沒有微透鏡平坦化層300這點是和第2實施形態的固態攝影元件2相異。此外，半導體基板10、濾色器100、濾色器平坦化層40、微透鏡200及分隔壁50因為是和在第1實施形態及第2實施形態說明過的各部分相同的構成，故省略說明。<Modifications>Hereinafter, a modification of the second embodiment of the present invention will be described with reference to FIG. 4. As shown in FIG. 3, although the solid-state imaging element 2 of this embodiment has amicrolens flattening layer 300, it is not limited to this structure.For example, as shown in FIG. 4, a solid-state imaging element 2A of a modification of the second embodiment includes asemiconductor substrate 10, acolor filter 100, a colorfilter flattening layer 40, amicrolens 200, and apartition wall 50. That is, it is different from the solid-state imaging element 2 of the second embodiment in that there is nomicrolens flattening layer 300.In addition, since thesemiconductor substrate 10, thecolor filter 100, the colorfilter flattening layer 40, themicrolens 200, and thepartition wall 50 have the same configuration as those described in the first embodiment and the second embodiment, they are omitted Description.

＜第2實施形態的效果＞本實施形態的固態攝影元件2中，在濾色器100與微透鏡200之間，設有濾色器平坦化層40。因此，濾色器平坦化層40緩和來自其他層的應力，且可使微透鏡200的下面平坦，可適當形成微透鏡200。又，就本實施形態的固態攝影元件2而言，具有擴大第1微透鏡層20之形成條件的範圍之優點。具體言之，具有在使用電漿CVD等之成膜裝置時可提高成膜溫度的優點。無機材料等因為會有內含的應力等依成膜溫度而變化的傾向，故如上述可獲得濾色器平坦化層40緩和應力等之效果。因此，即便成膜溫度比設定溫度還稍有變動，仍可獲得在品質上不發生問題的效果。<Effects of the second embodiment>In the solid-state imaging element 2 of this embodiment, a colorfilter flattening layer 40 is provided between thecolor filter 100 and themicrolens 200. Therefore, the colorfilter flattening layer 40 relaxes stress from other layers, and can flatten the underside of themicrolens 200, and themicrolens 200 can be formed appropriately.In addition, the solid-state imaging element 2 of the present embodiment has an advantage of expanding the range of conditions for forming thefirst microlens layer 20. Specifically, it has an advantage that the film forming temperature can be increased when a film forming apparatus such as plasma CVD is used. Inorganic materials and the like tend to have internal stress and the like that change depending on the film forming temperature. Therefore, as described above, the colorfilter flattening layer 40 has the effect of alleviating stress and the like. Therefore, even if the film-forming temperature is slightly changed from the set temperature, the effect of no problem in quality can be obtained.

3.第3實施形態其次，針對本發明第3實施形態，使用圖5作說明。如圖5所示，本實施形態的固態攝影元件3係在微透鏡200具有設於第2微透鏡層21的上面之第3微透鏡層22這點和第1實施形態的固態攝影元件1相異。3. The third embodimentNext, the third embodiment of the present invention will be described with reference to FIG. 5. As shown in FIG. 5, the solid-state imaging element 3 of this embodiment is similar to the solid-state imaging element 1 of the first embodiment in that themicrolens 200 has athird microlens layer 22 provided on the upper surface of thesecond microlens layer 21. different.

以下，針對固態攝影元件3的構成，記載與第1實施形態中的固態攝影元件1的製造方法不同的部分。Hereinafter, regarding the configuration of the solid-state imaging element 3, the differences from the manufacturing method of the solid-state imaging element 1 in the first embodiment will be described.

(微透鏡)微透鏡200具有第1微透鏡層20、第2微透鏡層21、第3微透鏡層22。第1微透鏡層20及第2微透鏡層21係與第1實施形態的固態攝影元件1的第1微透鏡層20及第2微透鏡層21相同。第3微透鏡層22係減低因第1微透鏡層20所致之反射的層，具有比第2微透鏡層21還低的折射率。第3微透鏡層22較佳為氧含有量比第2微透鏡層21還高。(Micro lens)Themicrolens 200 has afirst microlens layer 20, asecond microlens layer 21, and athird microlens layer 22. Thefirst microlens layer 20 and thesecond microlens layer 21 are the same as thefirst microlens layer 20 and thesecond microlens layer 21 of the solid-state imaging element 1 of the first embodiment.Thethird microlens layer 22 is a layer that reduces the reflection caused by thefirst microlens layer 20 and has a refractive index lower than that of thesecond microlens layer 21. Thethird microlens layer 22 preferably has a higher oxygen content than thesecond microlens layer 21.

本實施形態中，雖示出微透鏡200係以3層所形成的構成，但只要是折射率從接近於光電轉換元件11的下層越往上層變越低的傾向，則多少層都沒有問題。又，在本實施形態中，和第1實施形態同樣地，雖示出在濾色器100與微透鏡200之間沒有濾色器平坦化層40的構成，但也可設有濾色器平坦化層40。In this embodiment, although themicrolens 200 has a three-layer structure, as long as the refractive index tends to decrease from the lower layer close to thephotoelectric conversion element 11 toward the upper layer, there is no problem with how many layers.In addition, in this embodiment, similar to the first embodiment, although the configuration in which the colorfilter flattening layer 40 is not provided between thecolor filter 100 and themicrolens 200 is shown, a color filter flattening layer may also be provided.化层40。 Thelayer 40.

(微透鏡之形成方法)迄至第1微透鏡層20的形成步驟為止係和第1實施形態相同。接下來，形成第2微透鏡層21。第二微透鏡係在折射率為1.5～1.75的範圍形成。接著，形成第3微透鏡層22。第3微透鏡層22係在折射率為1.3以上1.5以下形成。透過伴隨著從微透鏡的內側進到外側階段地降低折射率，縮小與空氣的折射率差，以減低在微透鏡的表面之反射。(Method of forming micro lens)The steps up to the formation of thefirst microlens layer 20 are the same as in the first embodiment. Next, thesecond microlens layer 21 is formed. The second microlens is formed in the range of refractive index of 1.5 to 1.75. Next, thethird microlens layer 22 is formed. Thethird microlens layer 22 is formed with a refractive index of 1.3 or more and 1.5 or less. By reducing the refractive index stepwise as it progresses from the inside to the outside of the microlens, the difference in refractive index with the air is reduced to reduce the reflection on the surface of the microlens.

第2以後的微透鏡可一層一層形成，亦可連續地形成。使用例如用電漿CVD形成的氮氧化矽，藉由以初期氮化物的比例多的條件形成且中途變為氧化物多的條件之方式變化氣體的流量等，來控制折射率亦可。The second and subsequent microlenses may be formed layer by layer, or may be formed continuously. For example, silicon oxynitride formed by plasma CVD may be used, and the refractive index may be controlled by changing the flow rate of the gas so that it is formed under a condition where the ratio of initial nitride is high and becomes a condition where there is much oxide in the middle.

又，藉由將第3微透鏡層22的膜厚設厚可變化折射率及微透鏡的形狀。藉由將微透鏡平坦化，省略後續步驟的微透鏡平坦化層300亦可使步驟容易。In addition, the refractive index and the shape of the microlens can be changed by setting the thickness of thethird microlens layer 22 thick. By flattening the microlens, omitting themicrolens flattening layer 300 in the subsequent steps can also make the steps easier.

使用第2以後的微透鏡賦予微透鏡平坦化層300的效果之情況，係亦可使用例如折射率1.2以上1.5以下程度的低折射率材料。When the second and subsequent microlenses are used to impart the effect of themicrolens flattening layer 300, for example, a low refractive index material having a refractive index of 1.2 or more and 1.5 or less can also be used.

藉由使用第3實施形態，可控制微透鏡的折射率，成為可控制聚光能力。By using the third embodiment, the refractive index of the microlens can be controlled, and the light-gathering ability can be controlled.

4.第4實施形態其次，針對本發明第4實施形態，使用圖6至圖8作說明。圖6表示本實施形態的固態攝影元件4的一構成例之平面圖。固態攝影元件4至少具備半導體基板10、濾色器100、微透鏡200A、及分隔壁50。固態攝影元件4係在取代微透鏡200而改為具備微透鏡200A這點與第1實施形態～第3實施形態的各固態攝影元件1～3相異。以下，針對微透鏡200A作詳細說明。此外，半導體基板10、濾色器100、濾色器平坦化層40及分隔壁50，因為是和在第1實施形態及第2實施形態說明過的各部分相同的構成故省略說明。4. Fourth EmbodimentNext, the fourth embodiment of the present invention will be described with reference to Figs. 6 to 8. FIG. 6 shows a plan view of a configuration example of the solid-state imaging element 4 of this embodiment. The solid-state imaging element 4 includes at least asemiconductor substrate 10, acolor filter 100, amicrolens 200A, and apartition wall 50. The solid-state imaging element 4 is different from the solid-state imaging elements 1 to 3 of the first to third embodiments in that it replaces themicrolens 200 with amicrolens 200A.Hereinafter, themicrolens 200A will be described in detail. In addition, since thesemiconductor substrate 10, thecolor filter 100, the colorfilter flattening layer 40, and thepartition wall 50 have the same configuration as those described in the first embodiment and the second embodiment, the description is omitted.

(微透鏡)微透鏡200A係和微透鏡200同樣地以複數(例如2層)的微透鏡層所形成。本實施形態中，針對微透鏡200A具備設在最接近於光電轉換元件11的下層之第1微透鏡層20A及設於第1微透鏡層20A的透鏡面上之第2微透鏡層21A的情況作說明。此外，第1微透鏡層20A及第2微透鏡層21A的剖面構成係和微透鏡200的第1微透鏡層20及第2微透鏡層21相同，在後述的圖6中，第1微透鏡層20A及第2微透鏡層21A未圖示出。(Micro lens)Themicrolens 200A system is formed with a plurality of (for example, two) microlens layers similarly to themicrolens 200. In this embodiment, the case where themicrolens 200A includes the first microlens layer 20A provided on the lower layer closest to thephotoelectric conversion element 11 and the second microlens layer 21A provided on the lens surface of the first microlens layer 20A Make a description. In addition, the cross-sectional configuration of the first microlens layer 20A and the second microlens layer 21A is the same as that of thefirst microlens layer 20 and thesecond microlens layer 21 of themicrolens 200. In FIG. 6 described later, the first microlens The layer 20A and the second microlens layer 21A are not shown.

微透鏡200A係具有與複數個光電轉換元件11分別對應的複數個透鏡。如圖6所示，微透鏡200A為，鄰接的複數個透鏡在平面圖中接觸著。微透鏡200A中，鄰接的複數個透鏡在平面圖中呈線狀接觸，但未必一定是呈線狀接觸。又，微透鏡200A亦可為，在構成濾色器100之第1濾色器14、第2濾色器15及第3濾色器16各自的角部上具有間隙(gap)，成為透鏡未覆蓋該角部上的形狀。又，微透鏡200A的填充因數(Fill Factor)較佳為80%以上100%以下，更佳為85%以上95%以下，該填充因數係表示透鏡覆蓋在具有光電轉換元件11的一個畫素上的比例。在填充因數為80%以上100%以下的情況，抑制因鄰接的透鏡間的間隙所致聚光特性之降低，綠(G)、藍(B)或紅(R)任一色的受光靈敏度皆提升，由於在85%以上95%以下受光靈敏度特別提升，故較佳。Themicrolens 200A has a plurality of lenses corresponding to the respectivephotoelectric conversion elements 11. As shown in FIG. 6, themicrolens 200A is such that a plurality of adjacent lenses are in contact with each other in a plan view. In the microlens 200A, a plurality of adjacent lenses are in linear contact in a plan view, but they are not necessarily in linear contact. In addition, themicrolens 200A may have gaps at the corners of thefirst color filter 14, thesecond color filter 15, and thethird color filter 16 constituting thecolor filter 100, and become a lens element. Cover the shape on the corner. In addition, the fill factor (Fill Factor) of themicrolens 200A is preferably 80% or more and 100% or less, more preferably 85% or more and 95% or less. The fill factor indicates that the lens covers one pixel with thephotoelectric conversion element 11 proportion. When the filling factor is 80% or more and 100% or less, the reduction in the light-gathering characteristics caused by the gap between adjacent lenses is suppressed, and the light receiving sensitivity of any color of green (G), blue (B) or red (R) is improved , It is better because the light receiving sensitivity is particularly improved above 85% and below 95%.

以下，參照圖7，針對填充因數作說明。圖7示意地顯示4個畫素及設置在各畫素P上的4個透鏡之平面構成的平面圖。填充因數係由以下式(1)所規定。填充因數［%］＝｛1－(a×a)/(A×A)｝×100　・・・(1)此處，A表示畫素尺寸，a表示在透鏡產生的間隙的對角線上之距離，且a＜A。又，填充因數係表示透鏡覆蓋在一個畫素上的比例，最大成為100%。Hereinafter, referring to FIG. 7, the filling factor will be described. FIG. 7 schematically shows a plan view of the plane configuration of 4 pixels and 4 lenses arranged on each pixel P. The filling factor is defined by the following formula (1).Filling factor [%]={1－(a×a)/(A×A)}×100　・・・(1)Here, A represents the pixel size, a represents the distance on the diagonal of the gap created by the lens, and a<A. In addition, the fill factor system represents the ratio of the lens covering one pixel, and the maximum is 100%.

以上那樣的微透鏡200A係可藉由使用隔著後述的透鏡基質來形成微透鏡的方法而形成。此外，如圖8所示，在未使用後述的透鏡基質下形成微透鏡(200’)的情況，各畫素P上的該微透鏡20’之鄰接的複數個透鏡彼此不接觸，複數個透鏡分別獨立地形成。在該情況，透鏡間的間隙G變大，難以使聚光效率提升。The above-mentionedmicrolens 200A can be formed by using a method of forming a microlens through a lens substrate described later.In addition, as shown in FIG. 8, when the microlens (200') is formed without using the lens substrate described later, the adjacent multiple lenses of the microlens 20' on each pixel P are not in contact with each other, and the multiple lenses They are formed independently. In this case, the gap G between the lenses becomes large, and it is difficult to improve the light collection efficiency.

＜第4實施形態的效果＞本實施形態中，固態攝影元件4因具備具有填充因數較佳為80%以上100以下、更佳為85%以上95%以下的透鏡之微透鏡200A，可使聚光特性提升。因微透鏡200A所具有的間隙所致之靈敏度特性的影響係在將微透鏡200A(第1微透鏡層20)的透鏡高度低時受到影響。因此，在第1微透鏡層20的膜厚為150nm以上400nm以下的情況中，藉由縮小透鏡間的間隙，可提供微細且更高靈敏度的固態攝影元件4。[實施例]<Effects of the fourth embodiment>In this embodiment, the solid-state imaging element 4 includes amicrolens 200A having a lens with a filling factor of preferably 80% or more and 100 or less, and more preferably 85% or more and 95% or less, so that the light-collecting characteristics can be improved. The influence of the sensitivity characteristic due to the gap of themicrolens 200A is affected when the lens height of themicrolens 200A (first microlens layer 20) is low. Therefore, when the film thickness of thefirst microlens layer 20 is 150 nm or more and 400 nm or less, by reducing the gap between the lenses, a finer and more sensitive solid-state imaging device 4 can be provided.[Example]

以下，針對本發明的固態攝影元件及習知的固態攝影元件作具體說明。＜實施例1＞實施例1中，說明和上述的第1實施形態的固態攝影元件1(參照圖1)同樣的製造方法。Hereinafter, the solid-state imaging device of the present invention and the conventional solid-state imaging device will be specifically described.<Example 1>In Example 1, the same manufacturing method as that of the solid-state imaging element 1 (see FIG. 1) of the first embodiment described above will be described.

首先，如圖9(a)至圖9(c)所示，準備半導體基板10，其具備呈二維配置的光電轉換元件11且各光電轉換元件11之間藉由元件分離構造12而使元件分離(圖9(a))。作為半導體基板10，使用光電轉換元件11的圖案尺寸為1μm以下的微細物。First, as shown in FIGS. 9(a) to 9(c), asemiconductor substrate 10 is prepared, which is provided withphotoelectric conversion elements 11 that are two-dimensionally arranged, and thephotoelectric conversion elements 11 are separated by anelement separation structure 12 between them. Separation (Figure 9(a)). As thesemiconductor substrate 10, a fine material having a pattern size of thephotoelectric conversion element 11 of 1 μm or less is used.

(分隔壁之形成)其次，在該半導體基板10上形成分隔壁50(圖9(b)、圖9(c))。首先，藉由電漿CVD成膜350nm膜厚的鎢膜。其次，於鎢膜上，將正型阻劑(TDMR-AR：東京應化工業股份有限公司製)使用旋轉塗布以1000rpm的旋轉數旋轉塗布之後，以90℃進行1分鐘預烘烤。藉此，製作將屬於感光性樹脂遮罩材料層(蝕刻遮罩)的光阻劑塗布了1.5μm膜厚的試樣。該屬於感光性樹脂遮罩材料層的正型阻劑係因紫外線照射使得紫外線照射部分起化學反應而溶解成顯影液。(Formation of the dividing wall)Next, apartition wall 50 is formed on the semiconductor substrate 10 (FIG. 9(b), FIG. 9(c)). First, a tungsten film with a thickness of 350 nm is formed by plasma CVD. Next, on the tungsten film, a positive resist (TDMR-AR: manufactured by Tokyo Ohka Kogyo Co., Ltd.) was spin-coated at a rotation speed of 1000 rpm using spin coating, and then prebaked at 90°C for 1 minute. In this way, a sample in which the photoresist belonging to the photosensitive resin mask material layer (etching mask) was coated with a film thickness of 1.5 μm was produced. The positive type resist, which belongs to the photosensitive resin mask material layer, is dissolved into a developing solution due to a chemical reaction of the ultraviolet irradiated part due to ultraviolet irradiation.

對該試樣進行隔介光罩執行曝光之光微影製程。曝光裝置係使用將i線波長使用於光源的曝光裝置。光微影製程中，對感光性樹脂遮罩材料層中之形成濾色器的部分照射紫外線。A photolithography process of exposure was performed on the sample with a dielectric mask. The exposure device uses an exposure device that uses the i-line wavelength as a light source. In the photolithography process, ultraviolet rays are irradiated to the part of the photosensitive resin mask material layer that forms the color filter.

其次，將2.38質量%的TMAH(四甲基氫氧化銨；tetramethylammonium hydroxide)用作顯影液進行顯影步驟，在形成濾色器的場所形成具有開口部的感光性樹脂遮罩層。在作為感光性樹脂遮罩材料層是使用正型阻劑的情況，以進行顯影後脫水烘烤(Dehydration Bake)，進行屬於感光性樹脂遮罩材料層的光阻劑之硬化者居多。本次係在120℃的溫度下實施脫水烘烤。感光性樹脂遮罩層係形成1.5μm的膜厚。Next, 2.38% by mass of TMAH (tetramethylammonium hydroxide) is used as a developing solution for a developing step, and a photosensitive resin mask layer having openings is formed at the place where the color filter is formed. In the case where a positive resist is used as the photosensitive resin mask material layer, most people perform the curing of the photoresist belonging to the photosensitive resin mask material layer by performing dehydration bake after development. This time, dehydration and baking were carried out at a temperature of 120°C. The photosensitive resin mask layer has a thickness of 1.5 μm.

其次，以感光性樹脂遮罩層為遮罩進行乾蝕刻。此時，所使用的乾蝕刻裝置係使用平行平板方式的乾蝕刻裝置。又，以對基底的半導體基板10不造成影響之方式在中途進行蝕刻條件的變更且以多階段實施乾蝕刻。Next, dry etching is performed using the photosensitive resin mask layer as a mask. At this time, the dry etching device used was a dry etching device of a parallel flat plate method. In addition, the etching conditions are changed in the middle so as not to affect theunderlying semiconductor substrate 10, and dry etching is performed in multiple stages.

一開始，使用氣體種類為混合SF₆、Ar兩種氣體而成的蝕刻氣體實施蝕刻。SF₆的氣體流量設為50ml/min，Ar的氣體流量設為100ml/min。又，將此時的腔室內的壓力設為2Pa的壓力，RF電源設為1000W來實施。使用該條件，蝕刻從感光性樹脂遮罩層露出的鎢膜的總膜厚200nm中的相當於90%的180nm程度。於該階段，變更成下個蝕刻條件。其次，使用SF₆、O₂、Ar三種氣體混合的蝕刻氣體實施蝕刻。將SF₆的氣體流量設為5ml/min、O₂的氣體流量設為50ml/min及Ar的氣體流量設為100ml/min，將從感光性樹脂遮罩層露出的鎢膜全部蝕刻除去。At the beginning, the etching is performed using an etching gas that is a mixture of SF_{6 and Ar.} The gas flow rate of SF₆ is set to 50 ml/min, and the gas flow rate of Ar is set to 100 ml/min. In addition, the pressure in the chamber at this time was set to a pressure of 2 Pa, and the RF power supply was set to 1000 W. Using this condition, about 180 nm, which is equivalent to 90%, of the total film thickness of 200 nm of the tungsten film exposed from the photosensitive resin mask layer is etched. At this stage, change to the next etching condition. Secondly, etching is performed using an etching gas mixed with three gases of_{SF 6} , O_{2, and Ar.} The gas flow rate of SF₆ was set to 5 ml/min,_{the gas flow rate of O 2} was set to 50 ml/min, and the gas flow rate of Ar was set to 100 ml/min, and all the tungsten film exposed from the photosensitive resin mask layer was etched and removed.

其次，進行除去作為蝕刻遮罩使用的感光性樹脂遮罩層。此時使用的方法係使用溶劑的方法，使用剝離液104(東京應化工業股份有限公司製)以噴霧洗淨裝置進行除去感光性樹脂遮罩層。其後，藉由氧電漿進行灰化，進行除去殘留中的感光性樹脂遮罩層。藉由此等步驟，在半導體基板上以格柵形狀形成具有鎢分隔壁構造之內側的膜厚(高度)350nm、寬度60nm的分隔壁30(圖9(b))。Next, the photosensitive resin mask layer used as an etching mask is removed. The method used at this time is a method using a solvent, and the photosensitive resin mask layer is removed with a spray cleaning device using the peeling solution 104 (manufactured by Tokyo Ohka Kogyo Co., Ltd.). After that, ashing is performed by oxygen plasma to remove the remaining photosensitive resin mask layer. Through these steps, apartition wall 30 having a thickness (height) of 350 nm and a width of 60 nm on the inside of the tungsten partition wall structure is formed in a grid shape on the semiconductor substrate (FIG. 9(b)).

其次，使用電漿CVD形成作為分隔壁31的SiO₂膜。此時使用的SiO₂之成膜條件係對鎢圖案(分隔壁30)使用在高度方向形成厚膜的條件。藉由分隔壁30和分隔壁31所形成的分隔壁50的高度為600nm(圖9(c))。_{Next, a SiO 2} film as thepartition wall 31 is formed using plasma CVD._{The film formation conditions of SiO 2} used at this time are conditions for forming a thick film in the height direction for the tungsten pattern (partition wall 30). The height of thepartition wall 50 formed by thepartition wall 30 and thepartition wall 31 is 600 nm (FIG. 9(c)).

(第1濾色器之形成)其次，進行形成第1濾色器14的第1濾色器形成步驟(圖10(a)、圖10(b))。首先，為了設置第1濾色器14，將含有綠(G)的顏料且具感光性的阻劑(以下，稱為綠色阻劑14a)塗布於半導體基板10的全面(圖10(a))。此時，亦可在綠色阻劑14a塗布前，對半導體基板10的全面施以用以提升密著性的疏水化表面處理(HMDS處理)。其次，在藉由光微影製程將綠色阻劑14a選擇性曝光後，進行顯影，形成和第1濾色器14形成位置對應之圖案的綠色濾色器。此時，作為綠色阻劑14a主成分的樹脂，使用已賦予感光性的丙烯酸系的樹脂。又，使用在綠色阻劑14a的顏料，分別在色指數(color index)為C.I.PG58、C.I.PY150，顏料濃度為60質量%。又，綠色濾色器的膜厚為600nm。(Formation of the first color filter)Next, the first color filter forming step of forming thefirst color filter 14 is performed (FIG. 10(a) and FIG. 10(b)).First, in order to install thefirst color filter 14, a photosensitive resist containing a green (G) pigment (hereinafter referred to as green resist 14a) is applied to the entire surface of the semiconductor substrate 10 (FIG. 10(a)) . At this time, before the green resist 14a is coated, the entire surface of thesemiconductor substrate 10 may be subjected to a hydrophobic surface treatment (HMDS treatment) for improving adhesion.Next, after selectively exposing the green resist 14a by a photolithography process, development is performed to form a green color filter having a pattern corresponding to the position where thefirst color filter 14 is formed. At this time, as the resin of the main component of the green resist 14a, an acrylic resin that has been imparted with photosensitivity is used. In addition, the pigments used in the green resist 14a have a color index of C.I.PG58 and C.I.PY150, and a pigment concentration of 60% by mass. In addition, the film thickness of the green color filter is 600 nm.

其次，為使綠色濾色器牢固地硬化，以熱板在230℃下進行6分鐘烘烤以進行硬化，形成第1濾色器14(圖10(b))。確認經該加熱步驟後，即使經過第3濾色器形成步驟等之步驟亦無第1濾色器14剝落或圖案崩塌等情況。Next, in order to harden the green color filter, it is cured by baking at 230°C for 6 minutes on a hot plate to form the first color filter 14 (FIG. 10(b)). It was confirmed that after this heating step, there was no peeling off or pattern collapse of thefirst color filter 14 even after the third color filter forming step and other steps.

(第2濾色器之形成)其次，進行形成第2濾色器15的第2濾色器形成步驟(圖11(a)、圖11(b))。為了設置第2濾色器15，將含有藍(B)的顏料且具感光性的阻劑(以下，稱為藍色阻劑)塗布於除了第1濾色器14形成區域以外的半導體基板10的全面(圖11(a))。此時，亦可在藍色阻劑塗布前，對半導體基板10的全面施以用以提升密著性的疏水化表面處理(HMDS處理)。其次，在藉由光微影製程將藍色阻劑選擇性曝光後，進行顯影，形成和第2濾色器15形成位置對應之藍色濾色器圖案。此時，作為藍色阻劑主成分的樹脂，使用以賦予感光性的丙烯酸系的樹脂。又，使用在藍色阻劑的顏料，分別在色指數(color index)為C.I.PB156、C.I.PV23，顏料濃度為50質量%。又，藍色濾色器的膜厚為590nm。(Formation of the second color filter)Next, a second color filter forming step of forming thesecond color filter 15 is performed (FIG. 11(a) and FIG. 11(b)).In order to provide thesecond color filter 15, a photosensitive resist containing a blue (B) pigment (hereinafter referred to as blue resist) is applied to thesemiconductor substrate 10 except for the region where thefirst color filter 14 is formed. The overall situation (Figure 11(a)). At this time, before the blue resist is applied, the entire surface of thesemiconductor substrate 10 may be subjected to a hydrophobic surface treatment (HMDS treatment) to improve adhesion.Next, after selectively exposing the blue resist by a photolithography process, development is performed to form a blue color filter pattern corresponding to the position where thesecond color filter 15 is formed. At this time, as the resin of the main component of the blue resist, an acrylic resin for imparting photosensitivity is used. In addition, the pigments used in the blue resist have a color index (color index) of C.I.PB156 and C.I.PV23, and a pigment concentration of 50% by mass. In addition, the film thickness of the blue color filter is 590 nm.

其次，為使藍色濾色器牢固地硬化，以熱板在230℃下進行6分鐘烘烤以進行硬化，形成第2濾色器15(圖11(b))。確認經該加熱步驟後，即使經過第3濾色器形成步驟等之步驟亦無第2濾色器15剝落或圖案崩塌等情況。Next, in order to harden the blue color filter firmly, thesecond color filter 15 is formed by baking it with a hot plate at 230°C for 6 minutes to form the second color filter 15 (FIG. 11(b)). It was confirmed that after this heating step, there was no peeling off or pattern collapse of thesecond color filter 15 even after the third color filter forming step and other steps.

(第3濾色器之形成)其次，進行形成第3濾色器16的第3濾色器形成步驟(圖12(a)、圖12(b))。為了設置第3濾色器16，將含有紅(R)的顏料且具感光性的阻劑(以下，稱為紅色阻劑)塗布於除了第1濾色器14及第2濾色器15形成區域以外的半導體基板10的全面(圖12(a))。此時，亦可在紅色阻劑塗布前，對半導體基板10的全面施以用以提升密著性的疏水化表面處理(HMDS處理)。其次，在藉由光微影製程將紅色阻劑選擇性曝光後，進行顯影，形成和第3濾色器16形成位置對應的紅色濾色器圖案。此時，作為紅色阻劑主成分的樹脂，使用已賦予感光性的丙烯酸系的樹脂。又，使用在紅色阻劑的顏料，分別在色指數(color index)為C.I.PR254、C.I.PY139，顏料濃度為60質量%。又，紅色濾色器的膜厚為610nm。(Formation of the third color filter)Next, a third color filter forming step of forming thethird color filter 16 is performed (FIG. 12(a), FIG. 12(b)).In order to install thethird color filter 16, a photosensitive resist containing a red (R) pigment (hereinafter referred to as red resist) is applied to thefirst color filter 14 and thesecond color filter 15 to form a photosensitive resist. The entire area of thesemiconductor substrate 10 outside the region (FIG. 12(a)). At this time, before the red resist is applied, the entire surface of thesemiconductor substrate 10 may be subjected to a hydrophobic surface treatment (HMDS treatment) for improving adhesion.Secondly, after the red resist is selectively exposed by a photolithography process, development is performed to form a red color filter pattern corresponding to the position where thethird color filter 16 is formed. At this time, as the resin of the main component of the red resist, an acrylic resin that has been imparted with photosensitivity is used. In addition, the pigments used in the red resist have color indexes of C.I.PR254 and C.I.PY139, and the pigment concentration is 60% by mass. In addition, the film thickness of the red color filter is 610 nm.

其次，為使紅色濾色器牢固地硬化，以熱板在230℃下進行6分鐘烘烤以進行硬化，形成第3濾色器16(圖12(b))。此時，確認了紅色濾色器因為周圍被矩形性良好的綠色濾色器及分隔壁50所包圍且矩形性良好地形成，所以在開口的底面及周圍之間密著性良好地硬化。藉由以上，形成具備第1濾色器14、第2濾色器15、第3濾色器16的濾色器100。Next, in order to harden the red color filter firmly, a hot plate is used for curing at 230°C for 6 minutes to form a third color filter 16 (FIG. 12(b)). At this time, it was confirmed that the red color filter is surrounded by the green color filter with good rectangularity and thepartition wall 50 and is formed with good rectangularity. Therefore, it is hardened with good adhesion between the bottom surface of the opening and the periphery.With the above, thecolor filter 100 including thefirst color filter 14, thesecond color filter 15, and thethird color filter 16 is formed.

(微透鏡形成步驟)其次，進行形成微透鏡200的微透鏡形成步驟(圖13(a)～圖13(e))。在所形成的濾色器100上層，使用電漿CVD形成膜厚600nm的氮化矽(SiN)膜20a(圖13(a))。此時，利用電漿CVD的成膜溫度設為240℃。所形成的氮化矽膜20a的折射率為1.85、波長340nm以後的消光係數為1.0×10^-3以下。又，氮化矽膜20a的波長330nm的消光係數係4.0×10^-2，確認了在該區域會稍微吸收光。(Microlens Formation Step) Next, a microlens formation step for forming themicrolens 200 is performed (FIG. 13(a) to FIG. 13(e)). On the upper layer of the formedcolor filter 100, a silicon nitride (SiN)film 20a with a film thickness of 600 nm is formed by plasma CVD (FIG. 13(a)). At this time, the film formation temperature by plasma CVD was set to 240°C. The formedsilicon nitride film 20a has a refractive index of 1.85 and an extinction coefficient of 1.0×10^-3 or less after a wavelength of 340 nm. In addition, the extinction coefficient of thesilicon nitride film 20a at a wavelength of 330 nm was 4.0×10^-2 , and it was confirmed that light was slightly absorbed in this region.

其次，在已形成的氮化矽膜20a上，塗布具有鹼可溶性、感光性、熱回流性之樹脂而形成感光性犧牲層。其後，將感光性犧牲層使用光罩藉由光微影製程之工序予以圖案化後，以200℃作熱處理而形成屬犧牲層的透鏡基質20b。透鏡基質20b係設置複數個厚度約300nm的平滑的半圓形狀所形成(圖13(b))。Next, on the formedsilicon nitride film 20a, a resin having alkali solubility, photosensitivity, and heat reflow properties is coated to form a photosensitive sacrificial layer. After that, the photosensitive sacrificial layer is patterned by a photolithography process using a photomask, and then heat-treated at 200° C. to form alens substrate 20b that is a sacrificial layer. Thelens substrate 20b is formed by arranging a plurality of smooth semicircular shapes with a thickness of about 300 nm (FIG. 13(b)).

其次，使用屬氟氯烷系氣體的CF₄與C₃F₈的混合系氣體施以乾蝕刻，將透鏡基質20b的圖案轉印於氮化矽膜20a，形成第1微透鏡層20(圖13(c))。此時的蝕刻速率係與透鏡基質20b和氮化矽膜20a的蝕刻速率同等，以選擇比成為1的條件實施。乾蝕刻時間設為5分鐘。藉此，以從第1微透鏡層20的半圓形狀透鏡的頂點到半圓形狀透鏡的底面(紅色的第3濾色器16的上面)為止的高度成為300nm之方式形成第1微透鏡層20。_{Next, dry etching is performed using a mixed gas of CF 4} and C₃ F₈ which is a chlorofluorocarbon gas, and the pattern of thelens substrate 20b is transferred to thesilicon nitride film 20a to form the first microlens layer 20 (Fig. 13(c)). The etching rate at this time is equivalent to the etching rate of thelens substrate 20b and thesilicon nitride film 20a, and it is implemented under the condition that the selection ratio becomes one. The dry etching time is set to 5 minutes. Thereby, thefirst microlens layer 20 is formed so that the height from the apex of the semicircular lens of thefirst microlens layer 20 to the bottom surface of the semicircular lens (the upper surface of the red third color filter 16) becomes 300 nm.

其次，在第1微透鏡層20上層，使用作為成膜裝置的電漿CVD形成50nm膜厚的作為第2微透鏡層21的氧化矽(SiO₂)膜(圖13(d))。氧化矽膜的折射率為1.45。藉此，形成微透鏡200。_{Next, on the upper layer of the first microlens layer 20, a silicon oxide (SiO 2} ) film as thesecond microlens layer 21 with a thickness of 50 nm was formed using plasma CVD as a film forming device (FIG. 13(d)). The refractive index of the silicon oxide film is 1.45. Thereby, themicro lens 200 is formed.

其次，進行形成微透鏡平坦化層300的微透鏡平坦化層形成步驟(圖14)。微透鏡平坦化層300係使用例如折射率1.35的有機系樹脂所形成。將該有機系樹脂以旋轉塗布法旋轉塗布500nm的膜厚並將微透鏡200平坦化。此外，微透鏡平坦化層300未受該厚度所限，只要是比微透鏡200的凹凸的高度厚且可將該凹凸平坦化的厚度即可。藉由以上各步驟，形成實施例的固態攝影元件1。Next, a microlens flattening layer forming step of forming themicrolens flattening layer 300 is performed (FIG. 14 ).Themicrolens flattening layer 300 is formed using, for example, an organic resin having a refractive index of 1.35. The organic resin was spin-coated to a film thickness of 500 nm by a spin coating method to planarize themicrolens 200. In addition, themicrolens flattening layer 300 is not limited by the thickness, as long as it is thicker than the height of the unevenness of themicrolens 200 and can flatten the unevenness.Through the above steps, the solid-state imaging device 1 of the embodiment is formed.

按以上那樣獲得的固態攝影元件1係因微透鏡200為以高折射率的材料形成而使聚光能力提升、因消光係數小而使材料的光透射特性高、及因微透鏡200形成300nm的膜厚而在紅、藍、綠3色所有濾色器具有良好的靈敏度。The solid-state imaging element 1 obtained as described above has an improved light-gathering ability because themicrolens 200 is formed of a material with a high refractive index, the light transmission characteristics of the material are high due to a small extinction coefficient, and themicrolens 200 is formed with a thickness of 300 nm. The film is thick and all color filters in red, blue, and green have good sensitivity.

＜實施例2＞實施例2和實施例1不同點為，在濾色器100與微透鏡200之間具備濾色器平坦化層40。實施例2中，迄至形成濾色器100為止的各步驟係和迄至形成實施例1所載的濾色器100為止的各步驟(圖9(a)～圖12(b))相同。因此，以下，針對濾色器100形成後的構成作說明。<Example 2>The difference between Example 2 and Example 1 is that a colorfilter flattening layer 40 is provided between thecolor filter 100 and themicrolens 200. In Example 2, the steps up to the formation of thecolor filter 100 are the same as the steps up to the formation of thecolor filter 100 described in Example 1 (FIG. 9(a) to FIG. 12(b)). Therefore, the following describes the structure after thecolor filter 100 is formed.

在濾色器100上面形成濾色器平坦化層40(圖15(a))。濾色器平坦化層40係為了減低因紅、藍、綠三色所形成的濾色器100與分隔壁50的高度差異所致之凹凸、及為了緩和形成於濾色器100上層的微透鏡200之應力而形成。又，在以氮化矽形成微透鏡200的情況，微透鏡200的熱膨脹係數雖和濾色器100的熱膨脹係數不同，但亦有因設置濾色器平坦化層40而緩和熱膨脹係數之差的效果。本實施例中，調整含有丙烯酸樹脂的塗布液之黏度並以旋轉數1000rpm旋轉塗布，再用熱板以溫度230℃施以6分鐘的加熱處理使樹脂硬化，形成濾色器平坦化層40。此時的濾色器平坦化層40的膜厚為100nm，濾色器平坦化層40之可見光的透射率為99%。且濾色器平坦化層40的折射率為1.6。A colorfilter planarization layer 40 is formed on the color filter 100 (FIG. 15(a)). The colorfilter flattening layer 40 is to reduce the unevenness caused by the height difference between thecolor filter 100 and thepartition wall 50 formed by the three colors of red, blue, and green, and to alleviate the microlenses formed on thecolor filter 100. The stress of 200 is formed. In addition, when themicrolens 200 is formed of silicon nitride, although the thermal expansion coefficient of themicrolens 200 is different from the thermal expansion coefficient of thecolor filter 100, the difference in the thermal expansion coefficient may be alleviated by the colorfilter flattening layer 40. effect.In this embodiment, the viscosity of the coating liquid containing acrylic resin is adjusted and spin-coated at a rotation speed of 1000 rpm, and then a hot plate is used to heat the resin at a temperature of 230° C. for 6 minutes to harden the resin to form the colorfilter flattening layer 40. The film thickness of the colorfilter flattening layer 40 at this time is 100 nm, and the visible light transmittance of the colorfilter flattening layer 40 is 99%. And the refractive index of the colorfilter flattening layer 40 is 1.6.

第1微透鏡層20的形成步驟(圖15(b)～圖15(d))係和實施例1的第1微透鏡層20的形成步驟(圖13(a)～圖13(c))相同。又，第2微透鏡層21的形成步驟以後，係和實施例1的第2微透鏡層21的形成步驟以後(圖13(d)、圖14)相同。藉由以上各步驟，形成實施例2的固態攝影元件。實施例2中，因在第1微透鏡層20下層形成濾色器平坦化層40而容易緩和應力，在300mm的晶圓面內等之大小的試樣範圍具有第1微透鏡層20的形成條件擴大的優點。The steps of forming the first microlens layer 20 (FIG. 15(b) to FIG. 15(d)) and the steps of forming thefirst microlens layer 20 of Example 1 (FIG. 13(a) to FIG. 13(c)) the same. In addition, the steps after the formation of thesecond microlens layer 21 are the same as the steps after the formation of thesecond microlens layer 21 of Example 1 (FIG. 13(d), FIG. 14).Through the above steps, the solid-state imaging device of Example 2 is formed.In Example 2, since the colorfilter flattening layer 40 is formed under thefirst microlens layer 20, the stress is easily relieved, and thefirst microlens layer 20 is formed in the sample area of the size of the 300mm wafer surface. The advantages of expanding conditions.

＜實施例3＞實施例3和實施例1不同點為，在形成微透鏡200時，積層的微透鏡之層數為3層。實施例3中，迄至形成第1微透鏡層20為止的各步驟係和實施例1中迄至形成第1微透鏡層20為止的各步驟(圖9(a)～圖13(c))相同。因此，以下，針對第1微透鏡層20形成後的構成作說明。<Example 3>The difference between Example 3 and Example 1 is that when themicrolens 200 is formed, the number of layers of the laminated microlens is three. In Example 3, the steps up to the formation of thefirst microlens layer 20 and the steps up to the formation of thefirst microlens layer 20 in Example 1 (FIG. 9(a) to FIG. 13(c)) the same. Therefore, the structure after the formation of thefirst microlens layer 20 will be described below.

在形成第1微透鏡層20之後，使用作為成膜裝置的電漿CVD形成作為第2微透鏡層21的氮氧化矽(SiON)膜。在成膜氮化矽(SiN)膜時，雖在氣體種類方面是使用SiH₄、NH₃、N₂，但在成膜氮氧化矽(SiON)膜之情況，也加入N₂O氣體，且主要藉由改變N₂O氣體與其他氣體的流量比以控制氮氧化矽(SiON)膜的折射率。本實施例中，作為第2微透鏡層21，形成50nm的折射率1.68的氮氧化矽(SiON)膜。After thefirst microlens layer 20 is formed, a silicon oxynitride (SiON) film as thesecond microlens layer 21 is formed using plasma CVD as a film forming device. When forming a silicon nitride (SiN) film, although SiH₄ , NH₃ , and N₂ are used in terms of gas types, in the case of forming a silicon oxynitride (SiON) film, N₂ O gas is also added, and The refractive index of the silicon oxynitride (SiON) film is mainly controlled by changing_{the flow ratio of N 2 O gas and other gases.} In this embodiment, as thesecond microlens layer 21, a silicon oxynitride (SiON) film with a refractive index of 1.68 is formed at 50 nm.

其次，在第2微透鏡層21之上，使用電漿CVD成膜氧化矽(SiO₂)膜作為第3微透鏡層22(圖16(a))。氧化矽(SiO₂)膜的折射率為1.47，形成50nm膜厚。Next, on thesecond microlens layer 21, a silicon_{oxide (SiO 2} ) film formed by plasma CVD is used as the third microlens layer 22 (FIG. 16(a)). The refractive index of the silicon oxide (SiO₂ ) film is 1.47, and the film thickness is 50 nm.

將這以後的微透鏡平坦化層300和實施例1的微透鏡平坦化層300同樣(圖14)地形成(圖16(b))。藉此，形成微透鏡200。藉由以上各步驟，形成實施例3的固態攝影元件。本實施例中，因為將微透鏡200以多層形成，具有減低以高折射率材料形成的微透鏡200自體之反射率使受光靈敏度提升的優點。The subsequentmicrolens flattening layer 300 is formed in the same manner as themicrolens flattening layer 300 of Example 1 (FIG. 14) (FIG. 16(b)). Thereby, themicro lens 200 is formed.Through the above steps, the solid-state imaging device of Example 3 is formed.In this embodiment, since themicrolens 200 is formed in multiple layers, it has the advantage of reducing the self-reflectivity of themicrolens 200 formed of a high-refractive index material and improving the light-receiving sensitivity.

＜實施例4＞實施例4與實施例1不同點在於，在形成微透鏡200時，於作為第1微透鏡層20的氮化矽膜20a之上，藉由樹脂材料形成複數個透鏡會分別接觸的透鏡基質20e，再以透鏡基質20e為遮罩形成第1微透鏡層20這點、及沒有形成微透鏡平坦化層300這點。實施例4中，迄至形成第1濾色器14、第2濾色器15及第3濾色器16為止的各步驟係和實施例1(圖9(a)～圖12(b)、圖15(a))相同。因此，以下，針對在作為第1微透鏡層20的氮化矽膜20a形成以後作說明。<Example 4>The difference between Example 4 and Example 1 is that when themicrolens 200 is formed, on thesilicon nitride film 20a as thefirst microlens layer 20, a resin material is used to form a plurality oflens substrates 20e that will contact each other. Then, thefirst microlens layer 20 is formed with thelens substrate 20e as a mask, and themicrolens flattening layer 300 is not formed. In Example 4, the steps up to the formation of thefirst color filter 14, thesecond color filter 15 and thethird color filter 16 and the example 1 (FIG. 9(a) to FIG. 12(b), Figure 15(a)) is the same. Therefore, the following description will be given after the formation of thesilicon nitride film 20a as thefirst microlens layer 20.

如圖17(a)所示，在形成作為第1微透鏡層20的氮化矽膜20a後，在氮化矽膜20a之上藉由樹脂材料形成中間犧牲層20c。其次，如圖17(b)所示，在中間犧牲層20c之上藉由阻劑形成具有透鏡形狀的遮罩20d。接著，如圖17(c)所示，以遮罩20d為遮罩藉由乾蝕刻將中間犧牲層20c加工呈微透鏡形狀，形成透鏡基質20e。此時，以透鏡間的間隔變狹窄的方式對中間犧牲層20c轉印微透鏡形狀。接著，如圖17(c)所示，以被加工成微透鏡形狀的中間犧牲層20c(透鏡基質20e)為遮罩，藉由乾蝕刻將氮化矽膜20a加工成微透鏡形狀。藉此，形成第1微透鏡層20。最後，與實施例2同樣地，形成第2微透鏡層21，形成微透鏡200。此時，以填充因數成為90%之方式形成微透鏡200。藉由該方法，複數個透鏡間之間隙(gap)可形成極少的微透鏡200。藉由以上，形成固態攝影元件，其具有鄰接的複數個透鏡在平面圖中分別線接觸且第1濾色器14、第2濾色器15及第3濾色器16各自的角部上具有間隙的微透鏡200。As shown in FIG. 17(a), after thesilicon nitride film 20a as thefirst microlens layer 20 is formed, an intermediatesacrificial layer 20c is formed of a resin material on thesilicon nitride film 20a. Next, as shown in FIG. 17(b), amask 20d having a lens shape is formed by a resist on the intermediatesacrificial layer 20c. Next, as shown in FIG. 17(c), the intermediatesacrificial layer 20c is processed into a microlens shape by dry etching using themask 20d as a mask to form alens substrate 20e. At this time, the microlens shape is transferred to the intermediatesacrificial layer 20c so that the interval between the lenses becomes narrow. Next, as shown in FIG. 17(c), the middlesacrificial layer 20c (lens substrate 20e) processed into a microlens shape is used as a mask, and thesilicon nitride film 20a is processed into a microlens shape by dry etching. In this way, thefirst microlens layer 20 is formed. Finally, in the same manner as in Example 2, thesecond microlens layer 21 is formed, and themicrolens 200 is formed. At this time, themicrolens 200 is formed so that the filling factor becomes 90%. With this method, the gaps between a plurality of lenses can form veryfew microlenses 200.Through the above, a solid-state imaging device is formed which has a plurality of adjacent lenses in line contact with each other in a plan view, and each of thefirst color filter 14, thesecond color filter 15, and thethird color filter 16 has a gap at the corners.的微lens 200.

＜固態攝影元件之評價＞在形成上述的各實施例的固態攝影元件時，藉由變更乾蝕刻的透鏡基質的高度，可使第一微透鏡的高度成為可變。又，藉由變更透鏡基質的形狀可使微透鏡層的填充因數成為可變。因此，以表1所示的水準變更微透鏡的高度及填充因數，實施受光靈敏度評價。又，在比較方面，與未將高折射率材料應用於微透鏡而使用屬習知材料的有機系樹脂所形成的微透鏡之以下的習知構造作比較。固態攝影元件之評價，如表1所示，形成了試樣No.1至試樣No.19的各固態攝影元件。此處，試樣No.1至試樣No.5係習知構造的固態攝影元件，試樣No.6至試樣No.12係實施例2的構造的固態攝影元件，試樣No.13係實施例1的構造的固態攝影元件，試樣No.14係實施例3的構造的固態攝影元件，試樣No.15至試樣No.19係實施例4的構造的固態攝影元件。＜Evaluation of solid-state imaging components＞When forming the solid-state imaging device of each of the above-mentioned embodiments, by changing the height of the dry-etched lens substrate, the height of the first microlens can be made variable. In addition, the filling factor of the microlens layer can be made variable by changing the shape of the lens substrate. Therefore, the height and filling factor of the microlenses were changed at the levels shown in Table 1, and the light receiving sensitivity evaluation was performed. In addition, in terms of comparison, it is compared with the following conventional structure of a microlens formed using an organic resin that is a conventional material without applying a high-refractive index material to the microlens.The evaluation of the solid-state imaging element is as shown in Table 1. Each solid-state imaging element of Sample No. 1 to Sample No. 19 was formed. Here, Sample No. 1 to Sample No. 5 are solid-state imaging devices with a conventional structure, Sample No. 6 to Sample No. 12 are solid-state imaging devices with a structure of Example 2, and Sample No. 13 The solid-state imaging device with the structure of Example 1 is the sample No. 14 is the solid-state imaging device with the structure of Example 3, and the sample No. 15 to No. 19 are the solid-state imaging device with the structure of Example 4.

＜習知構造＞習知構造的固態攝影元件和各實施例的固態攝影元件之不同點為，微透鏡是以含有丙烯酸樹脂的有機系樹脂材料所形成。習知構造的固態攝影元件中之微透鏡係按以下那樣所形成。習知構造的固態攝影元件中之微透鏡，迄至濾色器形成步驟為止係利用和實施例1相同步驟(圖9(a)～圖12(b))所形成。其次，將含有丙烯酸樹脂的有機系樹脂材料旋轉塗布成膜厚1.0μm的厚度，再以230℃加熱硬化，形成有機系樹脂膜。＜Conventional structure＞The difference between the conventional solid-state imaging element and the solid-state imaging element of each embodiment is that the microlens is formed of an organic resin material containing acrylic resin.The microlens in the conventional solid-state imaging element is formed as follows. The microlens in the conventional solid-state imaging element is formed by the same steps as in Example 1 (FIG. 9(a) to FIG. 12(b)) up to the color filter forming step. Next, the organic resin material containing acrylic resin was spin-coated to a thickness of 1.0 μm, and then heated and cured at 230° C. to form an organic resin film.

其次，在已形成的有機系樹脂膜上，塗布具有鹼可溶性、感光性、熱回流性之樹脂而形成感光性犧牲層。其後，將感光性犧牲層使用光罩藉由光微影製程之工序予以圖案化後，以200℃作熱處理，形成透鏡基質。在從試樣No.1到試樣No.5中，形成設置有複數個厚度各自為約150nm到約500nm的平滑的半圓形狀之透鏡基質。Next, on the formed organic resin film, a resin having alkali solubility, photosensitivity, and heat reflow properties is coated to form a photosensitive sacrificial layer. Thereafter, the photosensitive sacrificial layer is patterned by a photolithography process using a photomask, and then heat-treated at 200° C. to form a lens matrix. In Sample No. 1 to Sample No. 5, a plurality of smooth semicircular lens substrates each having a thickness of about 150 nm to about 500 nm were formed.

其次，使用屬氟氯碳系(Chlorofluorocarbons)氣體的CF₄與C₃F₈的混合系氣體施以乾蝕刻，將透鏡基質的圖案在有機系樹脂膜轉印形狀，形成微透鏡。此時的蝕刻速率係與透鏡基質和有機系樹脂膜的蝕刻速率同等，以選擇比接近1的條件實施。乾蝕刻時間設為8分鐘。藉此，在試樣No.1到試樣No.5中，以從微透鏡的半圓形狀透鏡的頂點到半圓形狀透鏡的底面(紅色的第3濾色器16之上面)為止的高度分別成為從200nm到550nm(參照表1)之方式形成微透鏡。Next, dry etching is performed using a mixed gas of CF₄ and C₃ F_{8 that is} a Chlorofluorocarbons gas, and the pattern of the lens matrix is transferred to the organic resin film to form a microlens. The etching rate at this time is equivalent to the etching rate of the lens substrate and the organic resin film, and the selection ratio is close to 1. The dry etching time was set to 8 minutes. As a result, in Sample No. 1 to Sample No. 5, the heights from the apex of the semicircular lens of the microlens to the bottom surface of the semicircular lens (the upper surface of the red third filter 16) are respectively Microlenses were formed from 200nm to 550nm (refer to Table 1).

表1顯示試樣No.1到試樣No.19的各固態攝影元件的微透鏡材料及構造。Table 1 shows the material and structure of the microlens of each solid-state imaging element of Sample No. 1 to Sample No. 19.

[表1]No.微透鏡構造微透鏡材料折射率透鏡高度(nm)填充因數(%)1習知構造(比較用)有機樹脂1.6200952習知構造(比較用)有機樹脂1.6300953習知構造(比較用)有機樹脂1.6400954習知構造(比較用)有機樹脂1.6500955習知構造(比較用)有機樹脂1.6550956實施例2SiN1.85120757實施例2SiN1.85160758實施例2SiN1.85200759實施例2SiN1.853007510實施例2SiN1.854007511實施例2SiN1.855007512實施例2SiN1.855507513實施例1SiN1.853007514實施例3SiN1.853007515實施例4SiN1.852008016實施例4SiN1.852008517實施例4SiN1.852009018實施例4SiN1.852009519實施例4SiN1.85200100[Table 1] No. Micro lens structure Micro lens material Refractive index Lens height (nm) Filling factor (%) 1 Conventional structure (for comparison) Organic resin 1.6 200 95 2 Conventional structure (for comparison) Organic resin 1.6 300 95 3 Conventional structure (for comparison) Organic resin 1.6 400 95 4 Conventional structure (for comparison) Organic resin 1.6 500 95 5 Conventional structure (for comparison) Organic resin 1.6 550 95 6 Example 2 SiN 1.85 120 75 7 Example 2 SiN 1.85 160 75 8 Example 2 SiN 1.85 200 75 9 Example 2 SiN 1.85 300 75 10 Example 2 SiN 1.85 400 75 11 Example 2 SiN 1.85 500 75 12 Example 2 SiN 1.85 550 75 13 Example 1 SiN 1.85 300 75 14 Example 3 SiN 1.85 300 75 15 Example 4 SiN 1.85 200 80 16 Example 4 SiN 1.85 200 85 17 Example 4 SiN 1.85 200 90 18 Example 4 SiN 1.85 200 95 19 Example 4 SiN 1.85 200 100

表2顯示比較試樣No.1到試樣No.19的各固態攝影元件之受光靈敏度評價結果後之結果。試樣No.1到試樣No.19的各固態攝影元件之受光靈敏度，係顯示以微透鏡高度為200nm的習知構造的固態攝影元件(試樣No.1)之受光靈敏度為基準的情況的受光靈敏度之增減量。Table 2 shows the results after comparing the light-receiving sensitivity evaluation results of the solid-state imaging elements of Sample No. 1 to Sample No. 19. The light-receiving sensitivity of each solid-state imaging device of Sample No. 1 to Sample No. 19 is based on the light-receiving sensitivity of a conventional solid-state imaging device (sample No. 1) with a microlens height of 200 nm. The amount of increase or decrease in the sensitivity of light.

[表2]No.微透鏡構造透鏡高度(nm)受光靈敏度比較(相對於No.1)藍色綠色紅色1習知構造(比較用)2000.0%0.0%0.0%2習知構造(比較用)3004.8%8.5%3.0%3習知構造(比較用)4007.4%8.0%3.8%4習知構造(比較用)5008.9%9.1%2.2%5習知構造(比較用)5507.4%3.9%3.2%6實施例2120-2.9%1.7%-0.3%7實施例21604.5%7.6%8.1%8實施例22004.0%7.3%5.9%9實施例23006.3%9.7%11.1%10實施例24003.5%7.3%4.1%11實施例25005.1%6.0%3.7%12實施例2550-1.9%-2.6%1.2%13實施例13007.8%10.3%11.9%14實施例33007.9%10.3%12.2%15實施例42005.8%7.5%5.2%16實施例42006.5%10.2%10.1%17實施例42006.9%10.6%11.3%18實施例42007.0%12.0%12.7%19實施例42006.7%9.2%6.9%[Table 2] No. Micro lens structure Lens height (nm) Comparison of light receiving sensitivity (compared to No.1) bluegreen red 1 Conventional structure (for comparison) 200 0.0% 0.0% 0.0% 2 Conventional structure (for comparison) 300 4.8% 8.5% 3.0% 3 Conventional structure (for comparison) 400 7.4% 8.0% 3.8% 4 Conventional structure (for comparison) 500 8.9% 9.1% 2.2% 5 Conventional structure (for comparison) 550 7.4% 3.9% 3.2% 6 Example 2 120 -2.9% 1.7% -0.3% 7 Example 2 160 4.5% 7.6% 8.1% 8 Example 2 200 4.0% 7.3% 5.9% 9 Example 2 300 6.3% 9.7% 11.1% 10 Example 2 400 3.5% 7.3% 4.1% 11 Example 2 500 5.1% 6.0% 3.7% 12 Example 2 550 -1.9% -2.6% 1.2% 13 Example 1 300 7.8% 10.3% 11.9% 14 Example 3 300 7.9% 10.3% 12.2% 15 Example 4 200 5.8% 7.5% 5.2% 16 Example 4 200 6.5% 10.2% 10.1% 17 Example 4 200 6.9% 10.6% 11.3% 18 Example 4 200 7.0% 12.0% 12.7% 19 Example 4 200 6.7% 9.2% 6.9%

從試樣No.1到試樣No.5的結果，得到在習知構造中微透鏡高度設越高，多色的受光靈敏度更會提升之結果。然而，高度超過550nm的微透鏡在工序上形成困難且無法製作。又，試樣No.5的固態攝影元件(微透鏡高度550nm)係透鏡形狀不形成半球形狀而成為透鏡形狀崩塌的結果，受光靈敏度降低。在微透鏡的微細化比本次形成的固態攝影元件還更進展的情況，透鏡高度高的形狀變得更難形成。From the results of sample No.1 to sample No.5, the higher the height of the microlens in the conventional structure, the higher the light-receiving sensitivity of multicolor. However, microlenses with a height exceeding 550 nm are difficult to form and cannot be produced in the process. In addition, the solid-state imaging element (microlens height 550 nm) of sample No. 5 did not form a hemispherical lens shape, and as a result of the collapse of the lens shape, the light-receiving sensitivity was reduced. When the miniaturization of the microlens is more advanced than the solid-state imaging element formed this time, it becomes more difficult to form a shape with a high lens height.

其次，從試樣No.6到試樣No.12的結果，得到在實施例2的構成的固態攝影元件中，在微透鏡高度為120nm時綠色的受光靈敏度變高，微透鏡高度為150nm～500nm時受光靈敏度變得比習知構造(試樣No.1)還高的結果。又，在微透鏡高度為550nm時，受光靈敏度比習知構造(試樣No.1)還降低的結果。如同發明者們的見解，將微透鏡的折射率設高的情況，會呈現出有應射入鄰接畫素的光被透鏡所阻斷的情況且在所有濾色器的受光靈敏度不良化的情況。Next, from the results of Sample No. 6 to Sample No. 12, it is found that in the solid-state imaging device of the configuration of Example 2, the green light-receiving sensitivity becomes higher when the micro lens height is 120 nm, and the micro lens height is 150 nm to 150 nm. As a result, the light-receiving sensitivity becomes higher than that of the conventional structure (Sample No. 1) at 500 nm. In addition, when the height of the microlens is 550 nm, the light-receiving sensitivity is lower than that of the conventional structure (Sample No. 1). As the inventors have found, if the refractive index of the microlens is set high, the light that should enter the adjacent pixel is blocked by the lens, and the light receiving sensitivity of all the color filters is deteriorated. .

其次，經比較微透鏡高度為相同的試樣No.9、試樣No.13、試樣No.14後之結果，了解到在實施例1、實施例3的構成的試樣No.13、No.14特別能獲得高的受光靈敏度。在實施例2的構成之試樣No.9中，因在濾色器100與微透鏡200之間有不同折射率的濾色器平坦化層40，與試樣No.13、No.14(實施例1、3)比較，認為發生光的反射使受光靈敏度一部分降低。又，在試樣No.9中，藉由將濾色器平坦化層40形成100nm的膜厚，與具有其他實施例的構成之試樣No.13、No.14比較，亦假想從微透鏡200到光電轉換元件11為止的距離變長的影響。試樣No.9的受光靈敏度雖會從試樣No.13的受光靈敏度降低，但因在製造步驟中形成條件的幅度寬廣，所以具有製造容易的優點。試樣No.14(實施例3)係藉由將微透鏡以3層構造來形成，能獲得減低光在高折射率的微透鏡之表面反射的效果，受光靈敏度比試樣No.13(實施例1)還提升。就試樣No.14而言，雖然工序的步驟數增加，但可用作為提升受光靈敏度的構造。試樣No.15～試樣No.19係藉由將微透鏡層以實施例4的方法來形成，使微透鏡層的填充因數高到80%以上100%以下，可獲得受光靈敏度比起以實施例1～3的方法形成的情況還來得更高。Next, after comparing the results of Sample No. 9, Sample No. 13, and Sample No. 14 whose microlens heights are the same, it is found that Sample No. 13 and Sample No. 13 have the structure of Example 1 and Example 3. No. 14 can particularly obtain high light-receiving sensitivity.In sample No. 9 of the configuration of Example 2, because there is a colorfilter flattening layer 40 with a different refractive index between thecolor filter 100 and themicrolens 200, it is the same as the samples No. 13, No. 14 ( Comparing Examples 1 and 3), it is considered that light reflection occurs and the light receiving sensitivity is partially lowered. Moreover, in sample No. 9, by forming the colorfilter flattening layer 40 into a film thickness of 100 nm, compared with samples No. 13 and No. 14 having configurations of other embodiments, it is also assumed that the microlens The distance from 200 to thephotoelectric conversion element 11 becomes longer. Although the light-receiving sensitivity of sample No. 9 is lower than the light-receiving sensitivity of sample No. 13, it has the advantage of ease of manufacture because of the wide range of formation conditions in the manufacturing step.Sample No. 14 (Example 3) is formed by forming a microlens with a three-layer structure. The effect of reducing light reflection on the surface of a high-refractive microlens can be obtained. The light receiving sensitivity is higher than that of Sample No. 13 (implementation). Example 1) It also improves. In the case of sample No. 14, although the number of steps increased, it can be used as a structure to increase the light-receiving sensitivity.Sample No.15～Sample No.19 are formed by using the method of Example 4 to form the microlens layer. The filling factor of the microlens layer is higher than 80% and 100%, and the light receiving sensitivity can be obtained compared with The conditions of the methods of Examples 1 to 3 are even higher.

如表2所示，就具有填充因數為80%以上100%以下的微透鏡層之試樣No.15～試樣No.19的固態攝影元件而言，確認了關於任一色的受光靈敏度比較中都有5%以上的增加。又，就具有填充因數為80%以上100%以下的微透鏡層之固態攝影元件而言，綠(G)的受光靈敏度比較係成為有7.5%以上的增加。再者，就具有填充因數為85%以上95%以下的微透鏡層之試樣No.16到試樣No.18的固態攝影元件而言，任一色的受光靈敏度比較都成為有特高的吸收率。因此，較佳為使用具有鄰接的複數個透鏡分別接觸且填充因數為80%以上100%以下的濾色器微透鏡200之固態攝影元件。又更佳為使用具有鄰接的複數個透鏡分別接觸且在濾色器各自的角部上具有間隙並且填充因數為85%以上95%以下的微透鏡200之固態攝影元件。As shown in Table 2, it was confirmed that the solid-state imaging elements of Sample No. 15 to Sample No. 19 having a microlens layer with a filling factor of 80% or more and 100% or less are in comparison with the light-receiving sensitivity of any color. Both have an increase of more than 5%. In addition, for a solid-state imaging element having a microlens layer with a filling factor of 80% or more and 100% or less, the light-receiving sensitivity of green (G) is relatively increased by 7.5% or more. Furthermore, with regard to the solid-state imaging elements of Sample No. 16 to Sample No. 18, which have a microlens layer with a filling factor of 85% or more and 95% or less, the light-receiving sensitivity of any color has extremely high absorption. rate.Therefore, it is preferable to use a solid-state imaging element having acolor filter microlens 200 with a plurality of adjacent lenses in contact with each other and a filling factor of 80% to 100%. It is more preferable to use a solid-state imaging element having amicrolens 200 that has a plurality of adjacent lenses in contact with each other and has gaps at the corners of the color filters, and has a filling factor of 85% or more and 95% or less.

以上，藉由各實施形態說明了本發明，但本發明之範圍未受限於圖示、所記載之例示的實施形態，亦包含可帶來與本發明之目的均等效果的所有實施形態。再者，本發明之範圍未受限於請求項所記載之發明特徵的組合，能藉由所有揭示的各個特徵中的特定特徵的任何所期望的組合所形成。As mentioned above, the present invention has been explained with the respective embodiments, but the scope of the present invention is not limited to the illustrated embodiments described in the drawings and includes all embodiments that can bring about effects equal to the purpose of the present invention. Furthermore, the scope of the present invention is not limited to the combination of the features of the invention described in the claims, and can be formed by any desired combination of specific features among all the disclosed features.

又，從第1至第3實施形態中，濾色器100係全面塗布已賦予感光性的濾色器材料，藉由選擇性地曝光形成濾色器的部位，使之硬化而形成濾色器圖案。然而，濾色器材料未受限於此種構成。例如，如圖19所示，亦可使用在未賦予濾色器材料感光性之下使用熱硬化性樹脂等藉由加熱烘烤作硬化之後，以光阻劑形成遮罩圖案，僅就欲開口的位置之濾色器進行蝕刻予以除去的工序。又亦可將該乾蝕刻工序與使用感光性濾色器的微影工序併用。又亦可在各實施形態使用任意工序來形成濾色器。又，分隔壁50係以可形成和濾色器100相同高度之情況作說明，但亦可使用濾色器的一半左右的高度之分隔壁構造。In addition, in the first to third embodiments, thecolor filter 100 is coated with a color filter material that has been provided with photosensitivity on the entire surface, and the color filter is formed by selectively exposing the part where the color filter is formed and hardening it. pattern. However, the color filter material is not limited to this configuration. For example, as shown in Fig. 19, it is also possible to use thermosetting resin without imparting photosensitivity to the color filter material. After curing by heating and baking, a mask pattern is formed with a photoresist, and only the opening is required. The color filter at the position is etched and removed. It is also possible to use this dry etching process together with a photolithography process using a photosensitive color filter. In each embodiment, any process may be used to form a color filter. In addition, thepartition wall 50 is described in a case where it can be formed at the same height as thecolor filter 100, but a partition wall structure of about half the height of the color filter may also be used.

10:半導體基板11:光電轉換元件12:元件分離構造14:第1濾色器15:第2濾色器16:第3濾色器20:第1微透鏡層21:第2微透鏡層22:第3微透鏡層30,31,50:分隔壁40:濾色器平坦化層100:濾色器200:微透鏡300:微透鏡平坦化層10: Semiconductor substrate11: photoelectric conversion element12: Component separation structure14: The first color filter15: 2nd color filter16: 3rd color filter20: The first microlens layer21: 2nd micro lens layer22: 3rdmicro lens layer30, 31, 50: dividing wall40: Color filter flattening layer100: color filter200: Micro lens300: Microlens flattening layer

圖1係本發明第1實施形態的固態攝影元件的部分剖面圖。圖2係本發明第1實施形態的固態攝影元件的濾色器排列的部分平面圖。圖3係本發明第2實施形態的固態攝影元件的部分剖面圖。圖4係表示本發明第2實施形態的固態攝影元件的變形例之部分剖面圖。圖5係本發明第3實施形態的固態攝影元件的部分剖面圖。圖6係表示本發明第4實施形態的固態攝影元件的微透鏡層的一構成例之平面圖。圖7係表示本發明第4實施形態的固態攝影元件的一構成例之平面圖。圖8係表示藉由其他方法所形成的固態攝影元件的微透鏡層的一構成例之平面圖。圖9係表示本發明第1實施形態的固態攝影元件的製造步驟之步驟剖面圖，係表示迄至分隔壁構造形成步驟為止的圖。圖10係表示本發明第1實施形態的固態攝影元件的製造步驟之步驟剖面圖，係表示第1濾色器形成步驟之圖。圖11係表示本發明第1實施形態的固態攝影元件的製造步驟之步驟剖面圖，係表示第2濾色器形成步驟之圖。圖12係表示本發明第1實施形態的固態攝影元件的製造步驟之步驟剖面圖，係表示第3濾色器形成步驟之圖。圖13係表示本發明第1實施形態的固態攝影元件的製造步驟之步驟剖面圖，係表示微透鏡形成步驟之圖。圖14係表示本發明實施例1的固態攝影元件的製造步驟之步驟剖面圖，係表示微透鏡平坦化層形成步驟之圖。圖15係本發明實施例2的固態攝影元件的製造步驟剖面圖，係表示從濾色器層平坦化層形成微透鏡的步驟之圖。圖16係本發明實施例3的固態攝影元件的製造步驟剖面圖，係表示微透鏡形成步驟之圖。圖17係本發明實施例4的固態攝影元件的製造步驟剖面圖，係表示微透鏡形成步驟之圖。圖18係表示本發明實施例4的固態攝影元件的以樹脂材料所形成的透鏡基質形狀之平面圖。圖19係本發明其他實施形態的固態攝影元件的製造步驟剖面圖，係表示在未賦予濾色器感光性之下利用乾蝕刻形成的步驟之圖。Fig. 1 is a partial cross-sectional view of a solid-state imaging device according to a first embodiment of the present invention.Fig. 2 is a partial plan view of the color filter arrangement of the solid-state imaging element according to the first embodiment of the present invention.Fig. 3 is a partial cross-sectional view of a solid-state imaging device according to a second embodiment of the present invention.4 is a partial cross-sectional view showing a modification of the solid-state imaging device according to the second embodiment of the present invention.Fig. 5 is a partial cross-sectional view of a solid-state imaging device according to a third embodiment of the present invention.Fig. 6 is a plan view showing a configuration example of a microlens layer of a solid-state imaging device according to a fourth embodiment of the present invention.Fig. 7 is a plan view showing a configuration example of a solid-state imaging element according to a fourth embodiment of the present invention.FIG. 8 is a plan view showing a configuration example of a microlens layer of a solid-state imaging device formed by another method.9 is a cross-sectional view showing the steps of manufacturing the solid-state imaging device according to the first embodiment of the present invention, and is a view showing up to the step of forming a partition wall structure.10 is a cross-sectional view showing the steps of manufacturing the solid-state imaging device according to the first embodiment of the present invention, and is a view showing the steps of forming a first color filter.11 is a cross-sectional view showing the steps of manufacturing the solid-state imaging device according to the first embodiment of the present invention, and is a diagram showing the steps of forming a second color filter.12 is a cross-sectional view showing the steps of manufacturing the solid-state imaging device according to the first embodiment of the present invention, and is a view showing the steps of forming a third color filter.13 is a cross-sectional view showing the steps of manufacturing the solid-state imaging device according to the first embodiment of the present invention, and is a view showing the steps of forming a microlens.14 is a cross-sectional view showing the steps of manufacturing the solid-state imaging device according toEmbodiment 1 of the present invention, and is a view showing the steps of forming a microlens flattening layer.15 is a cross-sectional view of the manufacturing steps of the solid-state imaging device according toEmbodiment 2 of the present invention, and is a diagram showing the steps of forming a microlens from a color filter layer flattening layer.16 is a cross-sectional view of the manufacturing steps of the solid-state imaging device according toEmbodiment 3 of the present invention, and is a diagram showing the steps of forming a microlens.FIG. 17 is a cross-sectional view of the manufacturing steps of the solid-state imaging device according to Embodiment 4 of the present invention, and is a diagram showing the steps of forming a microlens.Fig. 18 is a plan view showing the shape of a lens matrix formed of a resin material of a solid-state imaging element according to Example 4 of the present invention.19 is a cross-sectional view of a manufacturing process of a solid-state imaging element according to another embodiment of the present invention, and is a diagram showing the process of forming by dry etching without imparting photosensitivity to the color filter.

1:固態攝影元件1: Solid-state imaging components

10:半導體基板10: Semiconductor substrate

11:光電轉換元件11: photoelectric conversion element

12:元件分離構造12: Component separation structure

14:第1濾色器14: The first color filter

15:第2濾色器15: 2nd color filter

16:第3濾色器16: 3rd color filter

20:第1微透鏡層20: The first microlens layer

21:第2微透鏡層21: 2nd micro lens layer

30,31,50:分隔壁30, 31, 50: dividing wall

100:濾色器100: color filter

200:微透鏡200: Micro lens

300:微透鏡平坦化層300: Microlens flattening layer

Claims (13)

Translated fromChinese

一種固態攝影元件，具備：半導體基板；複數個光電轉換元件，設於前述半導體基板且在平面圖中配置成矩陣狀；濾色器層，與前述複數個光電轉換元件分別對應配置之複數色的濾色器是按預先設定的規則圖案作二維配置；及微透鏡層，具有與前述複數色的濾色器及前述複數個光電轉換元件分別對應配置的複數個透鏡，前述微透鏡層具有：配置在最接近於前述光電轉換元件側的第1微透鏡層；及形成為積層於前述第1微透鏡層的透鏡面上的第2微透鏡層，前述第1微透鏡層係膜厚為150nm以上400nm以下、折射率為1.75以上2.15以下、且由氮化矽或氮氧化矽所形成，前述第2微透鏡層係由具有比前述第1微透鏡層還低的折射率之氮氧化矽或氧化矽所形成。A solid-state imaging element, including:Semiconductor substrateA plurality of photoelectric conversion elements are arranged on the aforementioned semiconductor substrate and arranged in a matrix in a plan view;In the color filter layer, the color filters of the plural colors respectively arranged corresponding to the aforementioned plural photoelectric conversion elements are arranged two-dimensionally according to a predetermined regular pattern; andThe microlens layer has a plurality of lenses arranged corresponding to the color filters of the plurality of colors and the plurality of photoelectric conversion elements, respectively,The microlens layer has: a first microlens layer arranged on the side closest to the photoelectric conversion element; and a second microlens layer formed to be laminated on the lens surface of the first microlens layer,The first microlens layer has a film thickness of 150 nm or more and 400 nm or less, a refractive index of 1.75 or more and 2.15 or less, and is formed of silicon nitride or silicon oxynitride,The second microlens layer is formed of silicon oxynitride or silicon oxide having a lower refractive index than the first microlens layer.如請求項1之固態攝影元件，其中前述第1微透鏡層的膜厚係150nm以上300nm以下。Such as the solid-state imaging element of claim 1, whereThe film thickness of the first microlens layer is 150 nm or more and 300 nm or less.如請求項1或2之固態攝影元件，其中前述第2微透鏡層的折射率係1.4以上1.75以下。Such as the solid-state imaging device of claim 1 or 2, whereThe refractive index of the second microlens layer is 1.4 or more and 1.75 or less.如請求項1至3中任一項之固態攝影元件，其中前述微透鏡層的填充因數為80%以上100%以下。Such as the solid-state imaging device of any one of claims 1 to 3, whereinThe filling factor of the aforementioned microlens layer is 80% or more and 100% or less.如請求項1至4中任一項之固態攝影元件，其中前述微透鏡層為，鄰接的前述複數個透鏡分別接觸著且在前述濾色器的角部上具有間隙。Such as the solid-state imaging element of any one of claims 1 to 4, whereinIn the microlens layer, the plurality of adjacent lenses are in contact with each other and have gaps at the corners of the color filter.如請求項1至5中任一項之固態攝影元件，其中具備濾色器平坦化層，其設在前述微透鏡與前述濾色器層之間且形成為和前述微透鏡對向的面變平坦。The solid-state imaging device according to any one of claims 1 to 5, which includes a color filter flattening layer, which is provided between the microlens and the color filter layer and is formed to face the microlens flat.如請求項6之固態攝影元件，其中前述濾色器平坦化層係利用折射率1.6以上1.8以下的樹脂所形成。Such as the solid-state imaging element of claim 6, whereinThe aforementioned color filter flattening layer is formed of a resin having a refractive index of 1.6 or more and 1.8 or less.如請求項1至7中任一項之固態攝影元件，其中具備透鏡平坦化層，其設在前述微透鏡層的透鏡面上且形成為上面變平坦。The solid-state imaging device according to any one of claims 1 to 7, which is provided with a lens flattening layer provided on the lens surface of the aforementioned microlens layer and formed so that the upper surface becomes flat.如請求項8之固態攝影元件，其中前述透鏡平坦化層係利用折射率1.1以上1.6以下的樹脂所形成。Such as the solid-state imaging element of claim 8, whereThe aforementioned lens flattening layer is formed of a resin having a refractive index of 1.1 or more and 1.6 or less.如請求項1至9中任一項之固態攝影元件，其中前述第2微透鏡層的膜厚係50nm以上150nm以下。Such as the solid-state imaging device of any one of claims 1 to 9, whereinThe film thickness of the second microlens layer is 50 nm or more and 150 nm or less.如請求項10之固態攝影元件，其中前述第2微透鏡層的膜厚對前述第1微透鏡層的膜厚之比率係0.125以上1.0以下。Such as the solid-state imaging element of claim 10, whereThe ratio of the film thickness of the second microlens layer to the film thickness of the first microlens layer is 0.125 or more and 1.0 or less.一種固態攝影元件的製造方法，具備：複數個光電轉換元件在平面圖中配置成矩陣狀，在將複數個前述光電轉換元件之間設有元件分離構造的半導體基板上的前述光電轉換元件包圍的位置，形成分隔壁之步驟；將複數色的濾色器分別形成在與被前述分隔壁包圍的前述光電轉換元件對應之位置的步驟；在前述濾色器及前述分隔壁的上部，形成膜厚為150nm以上400nm以下且折射率為1.75以上2.15以下的氮化矽膜或氮氧化矽膜，在與前述複數個光電轉換元件分別對應的位置形成複數個透鏡而形成第1微透鏡層的步驟；及在前述第1微透鏡層的透鏡面上，形成具有比起前述第1微透鏡層還低折射率的氮氧化矽膜或氧化矽膜而形成第2微透鏡層的步驟。A method for manufacturing a solid-state imaging element, including:A plurality of photoelectric conversion elements are arranged in a matrix in a plan view, and a partition wall is formed at a position surrounded by the photoelectric conversion elements on a semiconductor substrate with an element separation structure between the plurality of photoelectric conversion elements;A step of forming color filters of plural colors at positions corresponding to the photoelectric conversion elements surrounded by the partition walls;On the upper part of the color filter and the partition wall, a silicon nitride film or a silicon oxynitride film with a film thickness of 150 nm or more and 400 nm or less and a refractive index of 1.75 or more and 2.15 or less is formed. A step of forming a plurality of lenses in positions to form a first microlens layer; andOn the lens surface of the first microlens layer, a silicon oxynitride film or a silicon oxide film having a lower refractive index than that of the first microlens layer is formed to form a second microlens layer.如請求項12之固態攝影元件的製造方法，其中形成前述第1微透鏡的步驟係具有：藉由對按濾色器層、無機材料層、樹脂層及阻劑層之順序積層的積層體的前述阻劑層進行光微影製程，而在前述阻劑層形成圖案的步驟；藉由熱流使前述圖案熔融，而成形為透鏡形狀的步驟；以成形為前述透鏡形狀的圖案為遮罩，對前述樹脂層進行乾蝕刻，將前述樹脂層成形於透鏡基質的步驟；及以前述透鏡基質為遮罩，對前述無機材料層進行乾蝕刻，將前述無機材料層成形於微透鏡的步驟。Such as the method of manufacturing a solid-state imaging device of claim 12, whereinThe steps of forming the aforementioned first microlens include:The step of forming a pattern on the resist layer by performing a photolithography process on the resist layer of the laminated body laminated in the order of the color filter layer, the inorganic material layer, the resin layer and the resist layer;The step of melting the aforementioned pattern by heat flow to form a lens shape;The step of dry etching the resin layer with the pattern formed into the lens shape as a mask, and forming the resin layer on the lens substrate; andThe step of performing dry etching on the inorganic material layer using the lens substrate as a mask, and forming the inorganic material layer on the microlens.

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