【０００１】[0001]
【発明の属する技術分野】本発明は、半導体集積回路の
製造に使用される投影レンズのように、精密な複写に用
いるレンズに関する。The present invention relates to a lens used for precise copying, such as a projection lens used for manufacturing a semiconductor integrated circuit.
【０００２】[0002]
【発明が解決しようとする課題】集積回路の製造に使用
される投影レンズは、そのレンズの開口数及び使用され
る光の波長によって決まる最大限の解像力を持つことが
必要である。しかしそれだけではなく、レチクル、マス
ク等の投影原版（以下本明細書においてレチクルと総称
する。）上の微細なパターンの形状を、感光剤を塗布し
たウエハ、ガラスプレート等の感光基板（以下本明細書
においてウエハと総称する。）上に精密に投影する必要
があるために、像面の湾曲、歪曲、その他の収差も非常
に厳しく補正されていることが要求される。すなわち文
字通りの理想像にできるだけ近い像を作ることが求めら
れる。更にチップの大型化に伴い、包含する有効画面の
大きさも増大してきた。これらの必要を満たすためレン
ズ構成は複雑となり、およそ３０枚程のレンズを必要と
し、その設計、製造は益々困難の度合いを増している。
そこで本発明は、十分に大きな開口数を持ち、結像性能
がきわめて高く、しかもレンズ枚数が十分に少ない精密
複写レンズを提供することを課題とする。The projection lens used in the manufacture of integrated circuits must have a maximum resolution determined by the numerical aperture of the lens and the wavelength of the light used. However, the shape of a fine pattern on a projection original (hereinafter, collectively referred to as a “reticle” in the present specification) such as a reticle and a mask is not limited to this. In order to accurately project the image on a wafer, it is required that the curvature, distortion, and other aberrations of the image plane are also corrected very strictly. That is, it is required to create an image as close as possible to a literal ideal image. Furthermore, as the size of the chip has increased, the size of the effective screen to be included has also increased. In order to satisfy these needs, the lens configuration is complicated, and about 30 lenses are required, and the design and manufacture thereof are becoming more and more difficult.
Accordingly, an object of the present invention is to provide a precision copying lens having a sufficiently large numerical aperture, extremely high imaging performance, and a sufficiently small number of lenses.
【０００３】[0003]
【課題を解決するための手段】本発明者は上記課題を解
決するために研究を重ね、一般にダブルガウス型と呼ば
れるレンズ構成が、従来の投影レンズでは２組用いられ
ており、そのために全系のレンズ枚数が多くなっている
ことに着目した。そして、非球面レンズ面を２枚以上程
度導入することにより、開口数が０．６以上で良好な結
像性能を維持しながら、ダブルガウス型レンズ構成を１
組に減らすことができ、したがって全系のレンズ枚数を
劇的に減らすことができることを見出して、本発明を完
成するに至った。すなわち本発明は、縮小倍率側から拡
大倍率側に向けて、正屈折力の第１レンズ群と、正屈折
力の第２レンズ群とからなり、第１レンズ群は、少なく
とも１枚の負レンズと、少なくとも１面の非球面レンズ
面とを有し、全系で少なくとも２面の非球面レンズ面を
有し、縮小倍率側から拡大倍率側に向けて、縮小倍率側
に凸面を向けたレンズ面と、拡大倍率側に凹面を向けた
レンズ面と、縮小倍率側に凹面を向けたレンズ面と、拡
大倍率側に凸面を向けたレンズ面とを有するダブルガウ
ス型レンズ構成を、全系で１組のみ有し、該１組のダブ
ルガウス型レンズ構成は、第２レンズ群の中に配置され
ている、精密複写レンズである。このように最低２枚の
非球面レンズ面を採用することにより、投影レンズなど
の精密複写レンズの構成枚数を、例えば従来の半分すな
わち１５枚程度にまで減少させることができる。Means for Solving the Problems The inventor of the present invention has been studying in order to solve the above-mentioned problems, and two sets of lens structures generally called a double Gaussian type are used in a conventional projection lens. Noticed that the number of lenses of the lens was increased. By introducing about two or more aspherical lens surfaces, a double Gaussian lens configuration can be realized while maintaining good imaging performance with a numerical aperture of 0.6 or more.
The inventors have found that the number of lenses can be reduced to a set, and thus the number of lenses of the entire system can be dramatically reduced, and the present invention has been completed. That is, the present invention comprises a first lens unit having a positive refractive power and a second lens unit having a positive refractive power from the reduction magnification side to the enlargement magnification side, and the first lens group includes at least one negative lens. A lens having at least one aspherical lens surface, at least two aspherical lens surfaces in the entire system, and a convex surface facing the reduction magnification side from the reduction magnification side to the enlargement magnification side. A double Gaussian lens configuration having a surface, a lens surface with a concave surface facing the magnification side, a lens surface with a concave surface facing the reduction magnification side, and a lens surface with a convex surface facing the magnification side. Having only one set, the one set of double Gaussian lens arrangements is a precision copying lens located in the second lens group. By employing at least two aspheric lens surfaces in this way, the number of components of a precision copying lens such as a projection lens can be reduced to, for example, half of the conventional one, that is, to about fifteen.
【０００４】本発明による精密複写レンズを、半導体製
造用の投影レンズとして使用するときには、光線は拡大
倍率側（レチクル側）から縮小倍率側（ウエハ側）に進
むが、以下の説明では便宜上、縮小倍率側の物体（ウエ
ハ）から拡大倍率側の像面（レチクル）に光線が進むも
のとして説明する。本発明による精密複写レンズの基本
的構造は、大別して２つのレンズ群Ｇ1、Ｇ2からなる。
縮小倍率側すなわち物体側（ウエハ側）に配置した第１
レンズ群Ｇ1は、顕微鏡対物レンズの前群に近い形状を
与え、物体（ウエハ）から出た発散光線をほぼ平行状態
としている。他方、その後方の拡大倍率側（レチクル
側）に配置した第２レンズ群Ｇ2としては、現在、収差
の良く補正され最も信頼できるタイプとして知られてい
るダブルガウス型写真レンズを用いている。なおダブル
ガウス型のレンズ構成とは、左右対称なレンズ構成であ
り、したがっていずれの側から規定しても同じである
が、例えば縮小倍率側（ウエハ側）に凸面を向けたレン
ズ面ｒaと、拡大倍率側（レチクル側）に凹面を向けた
レンズ面ｒbと、縮小倍率側（ウエハ側）に凹面を向け
たレンズ面ｒcと、拡大倍率側（レチクル側）に凸面を
向けたレンズ面ｒdとを含み、これらのレンズ面ｒa、ｒ
b、ｒc、ｒdがその順に配置されたレンズ構成をいう。When the precision copying lens according to the present invention is used as a projection lens for semiconductor manufacturing, light rays travel from the magnification side (reticle side) to the reduction side (wafer side). The following description is based on the assumption that a light beam travels from an object (wafer) on the magnification side to an image plane (reticle) on the magnification side. The basic structure of the precision copying lens according to the present invention is roughly divided into two lens groups G1 and G2 .
The first arranged on the reduction magnification side, that is, on the object side (wafer side)
Lens group G1 gives a shape close to the front group of the microscope objective lens, and the divergent light beam emitted from the object (wafer) substantially parallel state. On the other hand, as the second lens group G2 disposed on the magnification side of the rear (reticle side), currently using a double Gauss-type camera lens known as well corrected most reliable type of aberration. Note that the lens arrangement of a double Gaussian is a symmetrical lens arrangement, thus it is the same be defined from either side, and a lens surface ra having a convex surface facing example the reduction ratio side (wafer side) , and a lens surface rb having a concave surface directed toward the magnification side (reticle side), towards a lens surface rc having a concave surface facing the reduction ratio side (wafer side), the convex surface on the magnification side (reticle side) lens Surface rd, and these lens surfaces ra , r
b, rc, rd refers to a lens disposed configured in this order.
【０００５】一般的に顕微鏡対物レンズは、サジタルコ
マが負に湾曲する傾向を持ち、ダブルガウス型のレンズ
は、これとは逆に、サジタルコマが正に湾曲する傾向を
持つ。したがってこれらのレンズを組み合わせること
で、サジタルコマが良好な状態に補正される。これが本
発明による光学系の基本的な構想である。しかし顕微鏡
対物レンズとガウス型レンズとを組み合わせれば、必ず
コマが補正されるというわけではない。つまり上の構造
は、必要条件ではあっても十分条件でない。また原型の
持つ形式そのままでは収差補正に限界があるし、両レン
ズ群Ｇ1、Ｇ2から発生する収差も出来るだけ小さいこと
が望ましい。In general, a microscope objective lens has a tendency for sagittal coma to curve negatively, and a double Gaussian lens, on the contrary, has a tendency for sagittal coma to curve positively. Therefore, by combining these lenses, the sagittal coma is corrected to a favorable state. This is the basic concept of the optical system according to the present invention. However, if a microscope objective lens and a Gaussian lens are combined, coma is not necessarily corrected. In other words, the above structure is a necessary condition but not a sufficient condition. In addition, there is a limit to aberration correction if the form of the prototype is used as it is, and it is desirable that aberrations generated from both lens groups G1 and G2 be as small as possible.
【０００６】先ず顕微鏡対物レンズを基本とする第１レ
ンズ群Ｇ1の構成は、原理的には不遊面の連続であり、
球面収差は元来良好に補正される特性を持っている。
０．６程度の開口数の光束を、大きな球面収差を発生さ
せずにほぼ並行状態に絞るには、屈折率を１．５として
約５枚の正レンズを要する。この場合の倍率は約５倍で
あるから、０．６の開口数に相当する光束は、およそ
０．１程度にまで絞られることとなる。しかしこのまま
では、顕微鏡対物レンズの特性をそのまま受け継いだも
のとなるから、サジタルコマは負へ湾曲する傾向を持つ
こととなる。そこでこの傾向を少なくし、大きなコマの
発生を防ぐため、本発明においては顕微鏡対物レンズに
対応する第１レンズ群Ｇ1に、少なくとも１枚の負レン
ズを導入している。但し負レンズを導入したために、第
１レンズ群Ｇ1の正のパワーが不足することとなるか
ら、第１レンズ群Ｇ1中の正レンズのパワーを増大させ
る必要が生じる。ここで正レンズの枚数を増加したので
は、本発明の目的を達成することができない。そこで本
発明においては、構成枚数を増加させることなく正レン
ズの曲率を強めてパワーを増し、それに因る収差の発生
は非球面を採用することにより防いだ。First, the configuration of the first lens group G1 based on a microscope objective lens is, in principle, a continuation of a playless surface.
Originally, spherical aberration has a characteristic of being well corrected.
In order to reduce a light beam having a numerical aperture of about 0.6 to a substantially parallel state without generating a large spherical aberration, about five positive lenses are required with a refractive index of 1.5. Since the magnification in this case is about five times, the luminous flux corresponding to a numerical aperture of 0.6 is reduced to about 0.1. However, in this state, the characteristics of the microscope objective lens are directly inherited, so that the sagittal coma tends to curve negatively. Therefore to reduce this tendency, in order to prevent the generation of a large frame, the first lens group G1 corresponding to the microscope objective lens in the present invention introduces at least one negative lens. However since the introduction of the negative lens, since the positive power of the first lens group G1 is to be insufficient, it is necessary to increase the power of the positive lens in the first lens group G1. Here, if the number of positive lenses is increased, the object of the present invention cannot be achieved. Therefore, in the present invention, the power is increased by increasing the curvature of the positive lens without increasing the number of constituent lenses, and the generation of aberrations due to this is prevented by employing an aspherical surface.
【０００７】このように第１レンズ群Ｇ1に含まれる負
レンズと非球面は、主として画面周辺部の像に発生しが
ちなコマの補正を目的としているので、比較的にレンズ
の有効径の小さい面にこれらを採用するのがよい。その
理由は、物体（ウエハ）の中心と周辺から出たそれぞれ
の光がレンズを通過する高さが、総体的により大きく異
なる故に、周辺部のコマの補正には有効であるからであ
る。すなわち物体（ウエハ）に比較的近い面を非球面と
することが望ましい。また第１レンズ群の具体的な構成
としては、縮小倍率側（ウエハ側）から拡大倍率側（レ
チクル側）に向けて順に、正レンズと、負レンズと、縮
小倍率側（ウエハ側）に凹面を向けた２枚の正メニスカ
スレンズとを有する構成とすることが好ましい。[0007] negative lens and aspheric contained this way the first lens group G1, since it is an object mainly peripheral portion of the screen image to the prone coma correction generation of the effective diameter of the lens is relatively It is better to employ these on small surfaces. The reason for this is that the height at which the respective light beams emitted from the center and the periphery of the object (wafer) pass through the lens is greatly different overall, which is effective for correcting the coma in the peripheral portion. That is, it is desirable that the surface relatively close to the object (wafer) be an aspheric surface. As a specific configuration of the first lens group, a positive lens, a negative lens, and a concave surface on the reduction magnification side (wafer side) are sequentially arranged from the reduction magnification side (wafer side) to the enlargement magnification side (reticle side). It is preferable to have a configuration having two positive meniscus lenses directed toward.
【０００８】第１レンズ群Ｇ1によってほぼ平行光とな
った光束は、正の屈折力を持つ第２レンズ群Ｇ2によっ
て像面（レチクル）上に結像する。ここでコマ収差の補
正を目的とした先の非球面とは別に、球面収差を良好に
補正する目的でもう１つの非球面を含ませる必要があ
る。この目的のためには有効径の大きい、光線のより広
がった面を非球面とするのが効率的である。両レンズ群
Ｇ1、Ｇ2の境界では光束は平行光に近く、すなわち光束
が広がっているから、両レンズ群Ｇ1、Ｇ2の境界近くの
面を非球面とすることが望ましい。以下の各実施例で
は、この非球面は第２レンズ群Ｇ2中に配置されている
が、両レンズ群Ｇ1、Ｇ2の境界近くの第１レンズ群Ｇ1
側のレンズ面を非球面とすることもできる。[0008] The light beam which has become substantially parallel by the first lens group G1 is imaged on an image plane (reticle) by the second lens group G2 having a positive refractive power. Here, it is necessary to include another aspherical surface in order to satisfactorily correct spherical aberration, in addition to the aspherical surface for the purpose of correcting coma aberration. For this purpose, it is efficient to make the surface with a larger effective diameter and the light beam spread more aspherical. At the boundary between the two lens groups G1 and G2 , the light flux is close to parallel light, that is, since the light flux is spread, it is desirable that the surface near the boundary between the two lens groups G1 and G2 be aspheric. In the following embodiments, the aspherical surface is arranged in the second lens group G2, but both lens group G1, G2 of the first lens group G1 near the boundary
The lens surface on the side may be aspherical.
【０００９】ダブルガウス型レンズを用いた第２レンズ
群Ｇ2は、ダブルガウス型の原型そのままとすることも
できるが、光線を緩やかに曲げるために、拡大倍率側
（レチクル側）に凹面を向けたレンズ面ｒbを有するレ
ンズと、縮小倍率側（ウエハ側）に凹面を向けたレンズ
面ｒcを有するレンズは、共にメニスカス負レンズとす
ることが好ましい。同様の理由により、レンズ面ｒbを
有するレンズとレンズ面ｒcを有するレンズの間に、少
なくとも１枚の負レンズを配置することが好ましく、更
には、この負レンズのうちの少なくとも１枚の負レンズ
を、両凹形状に形成することが好ましい。これらの構成
により、主としてコマに及ぼす悪影響を抑えつつ、ペッ
ツバール和を良好に補正することができる。The second lens group G2 using a double Gaussian lens can be a double Gaussian prototype as it is, but in order to bend light rays gently, the concave surface is directed to the magnification side (reticle side). a lens having a surface rb has a lens having a lens surface rc having a concave surface facing the reduction ratio side (wafer side), both it is preferable that the negative meniscus lens. For the same reason, while the lens having a lens and a lens surface rc having a lens surface rb, it is preferable to place at least one negative lens, and further, at least one of the negative lens It is preferable that the negative lens is formed in a biconcave shape. With such a configuration, the Petzval sum can be satisfactorily corrected while mainly suppressing an adverse effect on the frame.
【００１０】[0010]
【発明の実施の形態】本発明の実施の形態を図面によっ
て説明する。以下の各実施例は、本発明による精密複写
レンズを半導体露光装置の投影光学系に適用したもので
あり、図１、図３、図５、図７は、それぞれ第１〜第４
実施例の投影光学系の断面図を示す。各実施例の投影光
学系とも、レチクルＲ上のパターンを縮小倍率にてウエ
ハＷ上に投影露光するものであり、縮小倍率側すなわち
ウエハＷ側から拡大倍率側すなわちレチクル側に向け
て、正屈折力の第１レンズ群Ｇ1と、正屈折力の第２レ
ンズ群Ｇ2とからなる。開口絞りＡＳは両レンズ群Ｇ1、
Ｇ2の間に配置されている。また、図中＊印は非球面レ
ンズ面を表す。Embodiments of the present invention will be described with reference to the drawings. In each of the following embodiments, the precision copying lens according to the present invention is applied to a projection optical system of a semiconductor exposure apparatus. FIGS. 1, 3, 5, and 7 show first to fourth embodiments, respectively.
1 shows a cross-sectional view of a projection optical system according to an embodiment. Each of the projection optical systems according to the embodiments projects the pattern on the reticle R onto the wafer W at a reduction magnification, and performs positive refraction from the reduction magnification side, that is, the wafer W side, to the enlargement magnification side, that is, the reticle side. a first lens group G1 of the force, and a second lens group G2 Metropolitan of positive refractive power. The aperture stop AS has two lens groups G1 ,
It is disposed between the G2. In the drawing, the mark * indicates an aspheric lens surface.
【００１１】以下の表１〜表４に、それぞれ第１〜第４
実施例の諸元を示す。各表はウエハＷ側を物体面とし、
レチクルＲ側を像面として示したものであり、［主要諸
元］中、ｙは最大像高（レチクルＲ上での光線高）、Ｎ
Ａは物体側（ウエハＷ側）開口数を示す。［レンズ諸
元］中、第１欄Ｎｏは物体側（ウエハＷ側）からのレン
ズ面の番号、第２欄ｒは各レンズ面の曲率半径、第３欄
ｄは各レンズ面から次のレンズ面までの間隔、第４欄は
各レンズの番号、第５欄はガウス型レンズ構成のレンズ
面ｒa、ｒb、ｒc、ｒdを示す。Tables 1 to 4 show the first to fourth data, respectively.
The specifications of the embodiment will be described. In each table, the wafer W side is the object plane,
The reticle R side is shown as an image plane. In [main specifications], y is a maximum image height (light ray height on the reticle R), N
A indicates the object side (wafer W side) numerical aperture. In [Lens Specifications], the first column No is the number of the lens surface from the object side (wafer W side), the second column r is the radius of curvature of each lens surface, and the third column d is the next lens from each lens surface. distance to the surface, showing the fourth column is the number of each lens, the lens surface ra fifth column Gaussian lens configuration, rb, rc, the rd.
【００１２】また第１欄中＊印を付したレンズ面は非球
面を示し、非球面レンズ面についての第２欄ｒは、頂点
曲率半径である。非球面の形状は、ｙ：光軸からの高さ ｚ：接平面から非球面までの光軸方向の距離 ｒ：頂点曲率半径 κ：円錐係数 Ａ、Ｂ、Ｃ、Ｄ：非球面係数 によって表わしており、［非球面データ］に円錐係数κ
と非球面係数Ａ、Ｂ、Ｃ、Ｄを示した。すべての実施例
のすべてのレンズの硝材は合成石英であり、合成石英の
屈折率はｎ＝１．５０８３９である。またレンズの設計
波長λは、λ＝２４８．４ｎｍである。The lens surface marked with * in the first column indicates an aspherical surface, and the second column r for the aspherical lens surface indicates the radius of curvature of the vertex. The shape of the aspheric surface is y: height from the optical axis z: distance in the optical axis direction from the tangent plane to the aspherical surface r: vertex radius of curvature κ: conical coefficient A, B, C, D: aspherical surface coefficient Data] conic coefficient κ
And the aspheric coefficients A, B, C, and D are shown. The glass material of all the lenses in all the examples is synthetic quartz, and the refractive index of the synthetic quartz is n = 1.50839. The design wavelength λ of the lens is λ = 248.4 nm.
【００１３】各実施例とも、レンズＬ1〜Ｌ5までの５枚
のレンズが第１レンズ群Ｇ1に属し、レンズＬ6〜Ｌ15ま
での１０枚のレンズが第２レンズ群Ｇ2に属する。した
がって全系は１５枚のレンズによって構成されており、
従来例の構成枚数の半分となっている。第１実施例の第
１レンズ群Ｇ1は、正レンズＬ1と、負レンズＬ2と、縮
小倍率側（ウエハＷ側）に凹面を向けた３枚の正メニス
カスレンズＬ3〜Ｌ5からなり、１面の非球面レンズ面ｒ
3を有する。第２レンズ群Ｇ2は１面の非球面レンズ面ｒ
12を有する。また、ダブルガウス型レンズ構成のうち、
拡大倍率側（レチクルＲ側）に凹面を向けたレンズ面ｒ
bを有するレンズＬ9と、縮小倍率側（ウエハＷ側）に凹
面を向けたレンズ面ｒcを有するレンズＬ12は、共にメ
ニスカス負レンズであり、これらのレンズＬ9、Ｌ12の
間に、２枚の両凹レンズＬ10、Ｌ11が配置されている。In each embodiment,five lenses L1 to L5 belong to the first lens group G1 , and ten lenses L6 to L15 belong to the second lens group G2 . Belong. Therefore, the whole system is composed of 15 lenses,
This is half the number of components in the conventional example. The first lens group G1 of the first embodiment includes a positive lens L1, a negative lens L2, the three positive meniscus lens L3 ~L5 having a concave surface facing the reduction ratio side (wafer W side) And one aspheric lens surface r
With 3 . The second lens group G2 has one aspheric lens surface r.
With 12 . Also, of the double Gaussian lens configuration,
Lens surface r with concave surface facing magnification side (reticle R side)
a lens L9 having ab, a lens L12 having a lens surface rc having a concave surface facing the reduction ratio side (wafer W side) are both negative meniscus lens, between the lenses L9, L12 , biconcave lens L10 of two, L11 are disposed.
【００１４】第２実施例の第１レンズ群Ｇ1は、正レン
ズＬ1と、負レンズＬ2と、縮小倍率側（ウエハＷ側）に
凹面を向けた２枚の正メニスカスレンズＬ3、Ｌ4と、両
凸レンズＬ5からなり、１面の非球面レンズ面ｒ1を有す
る。第２レンズ群Ｇ2は１面の非球面レンズ面ｒ12を有
する。また、ダブルガウス型レンズ構成のうち、レンズ
面ｒbを有するレンズＬ9とレンズ面ｒcを有するレンズ
Ｌ12は、共にメニスカス負レンズであり、これらのレン
ズＬ9、Ｌ12の間に、２枚の両凹レンズＬ10、Ｌ11が配
置されている。The first lens group G1 of the second embodiment includes a positive lens L1 , a negative lens L2, and two positive meniscus lenses L3 having concave surfaces facing the reduction magnification side (wafer W side). and L4, made up of a double-convex lens L5, having an aspheric lens surface r1 of the first surface. The second lens group G2 having an aspherical lens surface r12 of the first surface. Also, of the double Gauss type lens configuration, a lens L12 having a lens L9 and the lens surface rc having a lens surface rb are both negative meniscus lens, between the lenses L9, L12, biconcave lens L10 of two, L11 are disposed.
【００１５】第３実施例の第１レンズ群Ｇ1は、正レン
ズＬ1と、負レンズＬ2と、縮小倍率側（ウエハＷ側）に
凹面を向けた２枚の正メニスカスレンズＬ3、Ｌ4と、両
凸レンズＬ5からなり、１面の非球面レンズ面ｒ1を有す
る。第２レンズ群Ｇ2は２面の非球面レンズ面ｒ12、ｒ
26を有する。また、ダブルガウス型レンズ構成のうち、
レンズ面ｒbを有するレンズＬ9とレンズ面ｒcを有する
レンズＬ12は、共にメニスカス負レンズであり、これら
のレンズＬ9、Ｌ12の間に、２枚の両凹レンズＬ10、Ｌ
11が配置されている。The first lens group G1 of the third embodiment includes a positive lens L1 , a negative lens L2, and two positive meniscus lenses L3 having concave surfaces facing the reduction magnification side (wafer W side). and L4, made up of a double-convex lens L5, having an aspheric lens surface r1 of the first surface. The second lens group G2 has two aspheric lens surfaces r12 and r12 .
Has 26 . Also, of the double Gaussian lens configuration,
Lens L12 having a lens L9 and the lens surface rc having a lens surface rb are both negative meniscus lens, between the lenses L9, L12, 2 pieces of a biconcave lens L10, L
11 are located.
【００１６】第４実施例の第１レンズ群Ｇ1は、正レン
ズＬ1と、負レンズＬ2と、縮小倍率側（ウエハＷ側）に
凹面を向けた３枚の正メニスカスレンズＬ3〜Ｌ5からな
り、３面の非球面レンズ面ｒ1、ｒ5、ｒ9を有する。第
２レンズ群Ｇ2は２面の非球面レンズ面ｒ15、ｒ19を有
する。また、ダブルガウス型レンズ構成のうち、レンズ
面ｒbを有するレンズＬ8とレンズ面ｒcを有するレンズ
Ｌ11は、共にメニスカス負レンズであり、これらのレン
ズＬ9、Ｌ12の間に、両凹レンズＬ10とメニスカスレン
ズＬ11が配置されている。The first lens group G1 of the fourth embodiment includes a positive lens L1 , a negative lens L2, and three positive meniscus lenses L3 to L3 having concave surfaces facing the reduction magnification side (the wafer W side). made L5, having an aspheric lens surface of the third surfacer 1, r 5, r 9 . The second lens group G2 having an aspherical lens surface r15, r19 of the two surfaces. Also, of the double Gauss type lens configuration, a lens L11 having a lens L8 and the lens surface rc having a lens surface rb are both negative meniscus lens, between the lenses L9, L12, biconcave lens L10 and the meniscus lens L11 is disposed.
【００１７】[0017]
【表１】 ［主要諸元］ ｙ＝54、 ＮＡ＝0 .63 ［レンズ諸元］ Ｎｏ ｒ ｄ 0 ∞ 12.000 Ｗ 1 -412.3737 32.015 Ｌ1 2 -48.0908 2.000 ＊ 3 -74.9914 9.000 Ｌ2 4 440.0919 33.447 5 -117.6334 26.050 Ｌ3 6 -86.5393 2.608 7 -185.4456 51.184 Ｌ4 8 -126.6760 58.837 9 -452.3392 45.000 Ｌ5 10 -174.0447 36.481 11 − 30.578 ＡＳ ＊12 863.8970 45.000 Ｌ6 13 -619.2023 26.007 14 624.7659 42.343 Ｌ7 15 -401.7493 2.000 16 175.5021 43.002 Ｌ8 ｒa 17 1229.9919 2.000 18 195.0359 65.000 Ｌ9 19 94.0609 21.600 ｒb 20 -298.7846 9.000 Ｌ10 21 74.6685 21.665 22 -181.7479 80.000 Ｌ11 23 370.2730 61.030 24 -94.4933 10.463 Ｌ12 ｒc 25 -223.7255 2.000 26 3080.5003 28.011 Ｌ13 27 -184.9088 2.000 ｒd 28 557.7267 27.021 Ｌ14 29 -313.1645 2.000 30 244.4765 66.204 Ｌ15 31 551.5976 104.452 32 ∞ Ｒ ［非球面データ］ Ｎｏ＝3 κ＝0.0 Ａ＝-0.838669×10-6 Ｂ＝-0.120851×10-9 Ｃ＝-0.221456×10-13 Ｄ＝-0.322104×10-17 Ｎｏ＝12 κ＝0.0 Ａ＝-0.133559×10-7 Ｂ＝ 0.112938×10-13 Ｃ＝-0.299594×10-18 Ｄ＝-0.157510×10-22[Table 1] [Main specifications] y = 54, NA = 0.63 [Lens specifications] Nord 0 ∞ 12.000 W 1 -412.3737 32.015 L1 2 -48.0908 2.000 * 3 -74.9914 9.000 L2 4 440.0919 33.4475 -117.6334 26.050 L 3 6 -86.5393 2.608 7 -185.4456 51.184 L 4 8 -126.6760 58.837 9 -452.3392 45.000 L 5 10 -174.0447 36.481 11 - 30.578 AS * 12 863.8970 45.000 L 6 13 -619.2023 26.007 14 624.7659 42.343 L 7 15-401.7493 2.000 16 175.5021 43.002 L 8 r a 17 1229.9919 2.000 18 195.0359 65.000 L 9 19 94.0609 21.600 r b 20 -298.7846 9.000 L 10 21 74.6685 21.665 22 -181.7479 80.000 L 11 23 370.2730 61.030 24 -94.4933 10.463 L 12 r c 25-223.7255 2.000 26 3080.5003 28.011 L 13 27 -184.9088 2.000 r d 28 557.7267 27.021 L 14 29 -313.1645 2.000 30 244.4765 66.204 L 15 31 551.5976 104.452 32 ∞ R [ aspherical data] No = 3 κ = 0.0 A = -0.838669 ×10 -6 B = -0.120851 × 10 -9 C = -0.221456 × 10 -13 D = -0.322104 × 10 -17 No = 12 κ = 0.0= -0.133559 × 10 -7 B = 0.112938 × 10 -13 C = -0.299594 × 10 -18 D = -0.157510 × 10 -22
【００１８】[0018]
【表２】 ［主要諸元］ ｙ＝54、 ＮＡ＝0 .63 ［レンズ諸元］ Ｎｏ ｒ ｄ 0 ∞ 12.000 Ｗ ＊ 1 -285.2904 19.137 Ｌ1 2 -54.4743 2.523 3 -77.4934 55.752 Ｌ2 4 -4040.8431 56.566 5 -336.3406 41.278 Ｌ3 6 -142.4889 2.000 7 -3794.5868 31.973 Ｌ4 8 -334.2358 2.000 9 1213.1931 45.000 Ｌ5 10 -388.8907 62.346 11 − 56.232 ＡＳ ＊12 15648.4082 45.000 Ｌ6 13 -422.4152 2.000 14 409.0829 41.395 Ｌ7 15 -826.4280 2.000 16 184.9031 44.411 Ｌ8 ｒa 17 1162.2125 2.000 18 172.1969 65.000 Ｌ9 19 97.7177 21.650 ｒb 20 -387.3645 15.000 Ｌ10 21 69.8491 22.975 22 -167.5942 80.000 Ｌ11 23 597.8696 52.022 24 -87.9543 15.000 Ｌ12 ｒc 25 -254.4693 2.000 26 1304.4999 26.721 Ｌ13 27 -206.8947 2.000 ｒd 28 588.3735 26.762 Ｌ14 29 -292.5931 2.000 30 242.0915 41.896 Ｌ15 31 730.7850 103.361 32 ∞ Ｒ ［非球面データ］ Ｎｏ＝1 κ＝0.0 Ａ＝-0.277552×10-6 Ｂ＝ 0.339384×10-9 Ｃ＝-0.213289×10-12 Ｄ＝ 0.870635×10-16 Ｎｏ＝12 κ＝0.0 Ａ＝-0.115626×10-7 Ｂ＝ 0.171661×10-13 Ｃ＝-0.470891×10-18 Ｄ＝-0.299676×10-23[Table 2] [Main specifications] y = 54, NA = 0 .63 [ Lens Data] No r d 0 ∞ 12.000 W * 1 -285.2904 19.137 L 1 2 -54.4743 2.523 3 -77.4934 55.752 L 2 4 -4040.843156.566 5 -336.3406 41.278 L 3 6 -142.4889 2.000 7 -3794.5868 31.973 L 4 8 -334.2358 2.000 9 1213.1931 45.000 L 5 10 -388.8907 62.346 11 - 56.232 AS * 12 15648.4082 45.000 L 6 13 -422.4152 2.000 14 409.0829 41.395 L 7 15-826.4280 2.000 16 184.9031 44.411 L 8 r a 17 1162.2125 2.000 18 172.1969 65.000 L 9 19 97.7177 21.650 r b 20 -387.3645 15.000 L 10 21 69.8491 22.975 22 -167.5942 80.000 L 11 23 597.8696 52.022 24 -87.9543 15.000 L 12 r c 25-254.4693 2.000 26 1304.4999 26.721 L 13 27 -206.8947 2.000 r d 28 588.3735 26.762 L 14 29 -292.5931 2.000 30 242.0915 41.896 L 15 31 730.7850 103.361 32 ∞ R [ aspherical data] No = 1 κ = 0.0 A = -0.277552 × 10-6 B = 0.339384 × 10-9 C = -0.213289 × 10-12 D = 0.870635 × 10-16 No = 12 κ = 0.0 A = -0.115626 × 10-7 B = 0.171661 × 10-13 C = -0.470891 × 10-18 D = -0.299676 × 10-23
【００１９】[0019]
【表３】 ［主要諸元］ ｙ＝54、 ＮＡ＝0 .63 ［レンズ諸元］ Ｎｏ ｒ ｄ 0 ∞ 12.000 Ｗ ＊ 1 -343.4103 38.622 Ｌ1 2 -94.8805 2.000 3 -265.0377 59.951 Ｌ2 4 762.1421 47.494 5 -424.8097 34.070 Ｌ3 6 -174.9866 2.000 7 -822.7865 34.312 Ｌ4 8 -237.0235 2.000 9 899.8952 45.000 Ｌ5 10 -364.8016 68.188 11 − 62.074 ＡＳ ＊12 1448.0526 45.000 Ｌ6 13 -504.8813 2.000 14 370.2340 43.211 Ｌ7 15 -801.1447 2.000 16 183.4536 41.299 Ｌ8 ｒa 17 878.5361 2.000 18 160.7184 57.613 Ｌ9 19 89.8972 23.758 ｒb 20 -323.3084 15.000 Ｌ10 21 71.7007 21.662 22 -182.7204 80.000 Ｌ11 23 386.3882 51.701 24 -83.4276 15.000 Ｌ12 ｒc 25 -182.5485 2.000 ＊26 2056.7360 26.345 Ｌ13 27 -204.0595 2.000 ｒd 28 420.5864 26.676 Ｌ14 29 -350.2068 2.000 30 237.0890 28.247 Ｌ15 31 515.2003 104.777 32 ∞ 100.006 Ｒ ［非球面データ］ Ｎｏ＝1 κ＝0.0 Ａ＝ 0.175468×10-6 Ｂ＝ 0.122760×10-9 Ｃ＝-0.757276×10-13 Ｄ＝ 0.201173×10-16 Ｎｏ＝12 κ＝0.0 Ａ＝-0.112281×10-7 Ｂ＝ 0.326511×10-13 Ｃ＝-0.382247×10-18 Ｄ＝-0.598689×10-23 Ｎｏ＝26 κ＝0.0 Ａ＝ 0.177749×10-7 Ｂ＝-0.769096×10-12 Ｃ＝-0.881895×10-18 Ｄ＝ 0.119522×10-20[Table 3] [Main specifications] y = 54, NA = 0 .63 [ Lens Data] No r d 0 ∞ 12.000 W * 1 -343.4103 38.622 L 1 2 -94.8805 2.000 3 -265.0377 59.951 L 2 4 762.1421 47.4945 -424.8097 34.070 L 3 6 -174.9866 2.000 7 -822.7865 34.312 L 4 8 -237.0235 2.000 9 899.8952 45.000 L 5 10 -364.8016 68.188 11 - 62.074 AS * 12 1448.0526 45.000 L 6 13 -504.8813 2.000 14 370.2340 43.211 L 7 15 -801.1447 2.000 16 183.4536 41.299 L 8 r a 17 878.5361 2.000 18 160.7184 57.613 L 9 19 89.8972 23.758 r b 20 -323.3084 15.000 L 10 21 71.7007 21.662 22 -182.7204 80.000 L 11 23 386.3882 51.701 24 -83.4276 15.000 L 12 r c 25 -182.5485 2.000 * 26 2056.7360 26.345 L 13 27 -204.0595 2.000 r d 28 420.5864 26.676 L 14 29 -350.2068 2.000 30 237.0890 28.247 L 15 31 515.2003 104.777 32 ∞ 100.006 R [ aspherical data] No = 1 κ = 0.0 A = 0.175468 × 10-6 B = 0.122760 × 10-9 C = -0.757276 × 10-13 D = 0.201173 × 10-16 No = 12 κ = 0.0 A = -0.112281 × 10-7 B = 0.326511 × 10-13 C = -0.382247 × 10-18 D = -0.598689 × 10-23 No = 26 κ = 0.0 A = 0.177749 × 10-7 B =- 0.769096 × 10-12 C = -0.881895 × 10-18 D = 0.119522 × 10-20
【００２０】[0020]
【表４】 ［主要諸元］ ｙ＝60、 ＮＡ＝0 .75 ［レンズ諸元］ Ｎｏ ｒ ｄ 0 ∞ 11.000 Ｗ ＊ 1 -451.9668 28.812 Ｌ1 2 -51.3422 2.106 3 -54.3232 98.270 Ｌ2 4 3964.7967 5.124 ＊ 5 -4129.6700 85.627 Ｌ3 6 -152.6636 1.000 7 -1109.5486 47.313 Ｌ4 8 -294.0002 1.000 ＊ 9 -1111.1011 61.292 Ｌ5 10 -265.6806 130.298 11 − 10.000 ＡＳ 12 1549.5637 42.510 Ｌ6 13 -3072.1449 2.651 14 477.7674 79.360 Ｌ7 ｒa ＊15 -332.1729 1.000 16 175.7794 100.173 Ｌ8 17 106.9303 34.731 ｒb 18 -380.1037 13.600 Ｌ9 ＊19 167.4018 28.351 20 -145.5550 150.000 Ｌ10 21 -2196.5821 36.153 22 -104.3517 52.125 Ｌ11 ｒc 23 -185.2823 1.000 24 15580.9719 41.656 Ｌ12 25 -278.1868 1.000 ｒd 26 311.7384 44.430 Ｌ13 27 -1507.9969 1.000 28 356.1569 56.523 Ｌ14 29 79374.1600 73.755 30 -442.6464 13.600 Ｌ15 31 659.8543 94.542 32 ∞ Ｒ ［非球面データ］ Ｎｏ＝1 κ＝0.0 Ａ＝ 0.150092×10-7 Ｂ＝-0.208705×10-10 Ｃ＝ 0.375337×10-13 Ｄ＝-0.148854×10-16 Ｎｏ＝5 κ＝0.0 Ａ＝-0.342906×10-7 Ｂ＝ 0.135963×10-11 Ｃ＝ 0.684686×10-17 Ｄ＝-0.684736×10-21 Ｎｏ＝9 κ＝0.0 Ａ＝-0.955961×10-8 Ｂ＝ 0.221468×10-13 Ｃ＝-0.105327×10-17 Ｄ＝-0.233395×10-22 Ｎｏ＝15 κ＝0.0 Ａ＝ 0.789729×10-8 Ｂ＝-0.116109×10-13 Ｃ＝ 0.356843×10-18 Ｄ＝ 0.175759×10-24 Ｎｏ＝19 κ＝0.0 Ａ＝ 0.687489×10-8 Ｂ＝ 0.107561×10-11 Ｃ＝ 0.856171×10-16 Ｄ＝ 0.586065×10-20[Table 4] [Main specifications] y = 60, NA = 0.75 [Lens specifications] Nord 0 ∞ 11.000 W * 1 -451.9668 28.812 L1 2 -51.3422 2.106 3 -54.3232 98.270 L2 4 3964.7967 5.124* 5 -4129.6700 85.627 L 3 6 -152.6636 1.000 7 -1109.5486 47.313 L 4 8 -294.0002 1.000 * 9 -1111.1011 61.292 L 5 10 -265.6806 130.298 11 - 10.000 AS 12 1549.5637 42.510 L 6 13 -3072.1449 2.651 14 477.7674 79.360 L 7r a * 15 -332.1729 1.000 16 175.7794 100.173 L 8 17 106.9303 34.731 r b 18 -380.1037 13.600 L 9 * 19 167.4018 28.351 20 -145.5550 150.000 L 10 21 -2196.5821 36.153 22 -104.3517 52.125 L 11 r c 23 -185.2823 1.000 2415580.9719 41.656 L 12 25 -278.1868 1.000 r d 26 311.7384 44.430 L 13 27 -1507.9969 1.000 28 356.1569 56.523 L 14 29 79374.1600 73.755 30 -442.6464 13.600 L 15 31 659.8543 94.542 32 ∞ R [ aspherical data] No = 1 κ = 0.0 A = 0.150092 × 10-7 B = -0.208705 × 10-10 C = 0.375337 × 10-13 D = -0.148854 × 10-16 No = 5 κ = 0.0 A = -0.342906 × 10-7 B = 0.135963 × 10-11 C = 0.684686 × 10-17 D = -0.684736 × 10-21 No = 9 κ = 0.0 A = -0.955961 × 10-8 B = 0.221468 x 10-13 C = -0.105327 x 10-17 D = -0.233395 x 10-22 No = 15 κ = 0.0 A = 0.789729 x 10-8 B = -0.116109 x 10-13 C = 0.356843 × 10-18 D = 0.175759 × 10-24 No = 19 κ = 0.0 A = 0.687489 × 10-8 B = 0.107561 × 10-11 C = 0.856171 × 10-16 D = 0.586065 × 10-20
【００２１】図２、図４、図６、図８にそれぞれ第１〜
第４実施例の球面収差、非点収差、及び歪曲収差を示
す。各収差図は、レチクルＲ側を像面とした収差図であ
る。非点収差図中点線はメリジオナル像面を表し、実線
はサジタル像面を表す。各収差図より明らかなように、
各実施例ともきわめて優れた結像性能を持つことが分か
る。FIGS. 2, 4, 6, and 8 show first to first examples, respectively.
13 shows spherical aberration, astigmatism, and distortion of the fourth example. Each aberration diagram is an aberration diagram with the reticle R side as an image plane. A dotted line in the astigmatism diagram represents a meridional image plane, and a solid line represents a sagittal image plane. As is clear from each aberration diagram,
It can be seen that each embodiment has extremely excellent imaging performance.
【００２２】[0022]
【発明の効果】以上のように本発明によれば、十分に大
きな開口数を持ち、結像性能がきわめて高く、しかもレ
ンズ枚数が十分に少ない精密複写レンズが得られる。As described above, according to the present invention, it is possible to obtain a precision copying lens having a sufficiently large numerical aperture, extremely high imaging performance, and a sufficiently small number of lenses.
【図１】本発明による精密複写レンズの第１実施例のレ
ンズ構成を示す断面図FIG. 1 is a sectional view showing a lens configuration of a first embodiment of a precision copying lens according to the present invention.
【図２】第１実施例の諸収差図FIG. 2 is a diagram showing various aberrations of the first embodiment.
【図３】第２実施例のレンズ構成を示す断面図FIG. 3 is a sectional view showing a lens configuration of a second embodiment.
【図４】第２実施例の諸収差図FIG. 4 is a diagram showing various aberrations of the second embodiment.
【図５】第３実施例のレンズ構成を示す断面図FIG. 5 is a sectional view showing a lens configuration of a third embodiment.
【図６】第３実施例の諸収差図FIG. 6 is a diagram showing various aberrations of the third embodiment.
【図７】第４実施例のレンズ構成を示す断面図FIG. 7 is a sectional view showing a lens configuration of a fourth embodiment.
【図８】第４実施例の諸収差図FIG. 8 is a diagram showing various aberrations of the fourth embodiment.
Ｌ1〜Ｌ15…レンズ Ｇ1、Ｇ2…レンズ群 Ｗ…ウエハ Ｒ…レチクル ＡＳ…開口絞り ＊…非球面レンズ面L1 ~L15 ... lens G1, G2 ... lens group W ... wafer R ... reticle AS ... aperture stop * aspheric lens surface
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP9163329AJPH10333030A (en) | 1997-06-04 | 1997-06-04 | Precision copy lens |
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP9163329AJPH10333030A (en) | 1997-06-04 | 1997-06-04 | Precision copy lens |
| Publication Number | Publication Date |
|---|---|
| JPH10333030Atrue JPH10333030A (en) | 1998-12-18 |
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP9163329APendingJPH10333030A (en) | 1997-06-04 | 1997-06-04 | Precision copy lens |
| Country | Link |
|---|---|
| JP (1) | JPH10333030A (en) |
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US6459534B1 (en) | 1999-06-14 | 2002-10-01 | Canon Kabushiki Kaisha | Projection optical system and projection exposure apparatus with the same, and device manufacturing method |
| US6556353B2 (en) | 2001-02-23 | 2003-04-29 | Nikon Corporation | Projection optical system, projection exposure apparatus, and projection exposure method |
| US6606144B1 (en) | 1999-09-29 | 2003-08-12 | Nikon Corporation | Projection exposure methods and apparatus, and projection optical systems |
| US6621555B1 (en) | 1999-06-14 | 2003-09-16 | Canon Kabushiki Kaisha | Projection optical system and projection exposure apparatus with the same, and device manufacturing method |
| US6674513B2 (en) | 1999-09-29 | 2004-01-06 | Nikon Corporation | Projection exposure methods and apparatus, and projection optical systems |
| US6862078B2 (en) | 2001-02-21 | 2005-03-01 | Nikon Corporation | Projection optical system and exposure apparatus with the same |
| US6867922B1 (en) | 1999-06-14 | 2005-03-15 | Canon Kabushiki Kaisha | Projection optical system and projection exposure apparatus using the same |
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US6459534B1 (en) | 1999-06-14 | 2002-10-01 | Canon Kabushiki Kaisha | Projection optical system and projection exposure apparatus with the same, and device manufacturing method |
| US6621555B1 (en) | 1999-06-14 | 2003-09-16 | Canon Kabushiki Kaisha | Projection optical system and projection exposure apparatus with the same, and device manufacturing method |
| US6867922B1 (en) | 1999-06-14 | 2005-03-15 | Canon Kabushiki Kaisha | Projection optical system and projection exposure apparatus using the same |
| US6606144B1 (en) | 1999-09-29 | 2003-08-12 | Nikon Corporation | Projection exposure methods and apparatus, and projection optical systems |
| US6674513B2 (en) | 1999-09-29 | 2004-01-06 | Nikon Corporation | Projection exposure methods and apparatus, and projection optical systems |
| US6864961B2 (en) | 1999-09-29 | 2005-03-08 | Nikon Corporation | Projection exposure methods and apparatus, and projection optical systems |
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| EP1235092A3 (en)* | 2001-02-23 | 2004-06-23 | Nikon Corporation | Projection optical system, projection apparatus and projection exposure method |
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| A621 | Written request for application examination | Free format text:JAPANESE INTERMEDIATE CODE: A621 Effective date:20040517 | |
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