CN103474538B - LED, its manufacture method and comprise its LED chip - Google Patents

Abstract

Translated fromChinese

本发明公开了一种LED外延片、其制作方法及包括其的LED芯片。该外延片包括：由衬底表面向外依次设置的未掺杂GaN层、N型GaN层、有源层以及P型GaN层，有源层包括一组或多组量子阱层，各量子阱层包括沿远离衬底的方向依次设置的InGaN势阱层、GaN势垒层和MgN势垒层。该方法包括以下步骤：由衬底表面向外依次形成未掺杂GaN层、N型GaN层、有源层以及P型GaN层，形成有源层的步骤包括依次形成一组或多组量子阱层，形成各量子阱层的步骤包括：由N型GaN层表面向外的方向，依次形成InGaN势阱层、GaN势垒层和MgN势垒层。采用本发明提供的LED外延片的制作方法所得到LED的亮度和内量子效率得到提升。

The invention discloses an LED epitaxial sheet, a manufacturing method thereof and an LED chip comprising the same. The epitaxial wafer includes: an undoped GaN layer, an N-type GaN layer, an active layer, and a P-type GaN layer arranged in sequence from the surface of the substrate outwards. The active layer includes one or more groups of quantum well layers, and each quantum well The layers include an InGaN potential well layer, a GaN potential barrier layer and a MgN potential barrier layer arranged in sequence along the direction away from the substrate. The method includes the following steps: sequentially forming an undoped GaN layer, an N-type GaN layer, an active layer, and a P-type GaN layer from the surface of the substrate outward, and the step of forming the active layer includes sequentially forming one or more sets of quantum wells The step of forming each quantum well layer includes: sequentially forming an InGaN potential well layer, a GaN barrier layer and a MgN barrier layer from the surface of the N-type GaN layer outward. The brightness and internal quantum efficiency of the LED obtained by adopting the manufacturing method of the LED epitaxial wafer provided by the invention are improved.

Description

Translated fromChinese

LED外延片、其制作方法及包含其的LED芯片LED epitaxial wafer, manufacturing method thereof, and LED chip comprising same

技术领域technical field

本发明涉及半导体照明技术领域，具体而言，涉及一种LED外延片、其制作方法及包含其的LED芯片。The invention relates to the technical field of semiconductor lighting, in particular to an LED epitaxial wafer, a manufacturing method thereof and an LED chip comprising the same.

背景技术Background technique

GaN基材料（包括GaN、AlGaN、InGaN、MgGaN、SiGaN）属于直接带隙半导体，并且其带隙从1.8～6.2V连续可调，是生产高亮度蓝光、绿光和白光LED的最常用材料，广泛应用于背光源、大尺寸屏幕显示、标示标牌指示、信号灯及照明等领域。GaN-based materials (including GaN, AlGaN, InGaN, MgGaN, and SiGaN) are direct bandgap semiconductors, and their bandgap is continuously adjustable from 1.8 to 6.2V. They are the most commonly used materials for producing high-brightness blue, green, and white LEDs. It is widely used in fields such as backlight, large-size screen display, signage indication, signal lamp and lighting.

GaN基LED芯片的制作方法通常为：采用MOCVD（金属有机化合物气相沉积）在衬底上外延生长一层GaN缓冲层；然后再生长非掺杂的GaN，目的是提高后续外延晶体的质量，在此基础上再依次生长N型GaN、有源层和P型GaN形成LED外延片，如图1所示。The manufacturing method of GaN-based LED chips is usually: use MOCVD (metal organic compound vapor deposition) to epitaxially grow a layer of GaN buffer layer on the substrate; then grow non-doped GaN, the purpose is to improve the quality of subsequent epitaxial crystals. On this basis, N-type GaN, active layer and P-type GaN are grown sequentially to form LED epitaxial wafers, as shown in Figure 1.

图1是现有的GaN基LED芯片的结构示意图，该芯片包括：设置在衬底10′上的未掺杂GaN层20′，包括GaN缓冲层21′和GaN层23′；设置在未掺杂GaN层20′上的N型GaN层30′，包括掺杂Al和Si的N型GaN层31′和掺杂Si的N型GaN层33′；设置在N型GaN层30′上的有源层40′，且有源层具有一组或多组量子阱层，每组量子阱层由InGaN势阱层41′和GaN势垒层43′组成；设置在有源层40′上的P型GaN层50′，包括掺杂Al和Mg的P型GaN层51′、掺杂Mg的P型GaN层53′以及P型GaN接触层55′。Fig. 1 is a schematic structural view of an existing GaN-based LED chip, which includes: an undoped GaN layer 20' disposed on a substrate 10', including a GaN buffer layer 21' and a GaN layer 23'; The N-type GaN layer 30' on the doped GaN layer 20' includes an N-type GaN layer 31' doped with Al and Si and an N-type GaN layer 33' doped with Si; The source layer 40', and the active layer has one or more groups of quantum well layers, each group of quantum well layers is composed of an InGaN potential well layer 41' and a GaN barrier layer 43'; the P disposed on the active layer 40' The P-type GaN layer 50' includes a P-type GaN layer 51' doped with Al and Mg, a P-type GaN layer 53' doped with Mg, and a P-type GaN contact layer 55'.

目前，在生长有源区的过程中，InGaN势阱层的结晶质量较差，导致有源区中存在很多晶格缺陷，比如数量约为10⁹cm^-2的位错。这些晶格缺陷会产生杂质电离、激发散射和晶格散射等问题，进而导致有源区中的非辐射复合中心增加，降低LED的内量子效率以及发光效率。At present, in the process of growing the active region, the crystalline quality of the InGaN potential well layer is poor, resulting in many lattice defects in the active region, such as dislocations with a quantity of about 10⁹ cm^-2 . These lattice defects will cause problems such as impurity ionization, excitation scattering and lattice scattering, which will lead to the increase of non-radiative recombination centers in the active region and reduce the internal quantum efficiency and luminous efficiency of LEDs.

发明内容Contents of the invention

本发明旨在提供一种LED外延片、其制作方法及包括其的LED芯片，以解决现有LED器件存在的有源层结晶质量差、晶格缺陷多的技术问题。The present invention aims to provide an LED epitaxial wafer, a manufacturing method thereof and an LED chip including the same, so as to solve the technical problems of poor crystallization quality of an active layer and many lattice defects existing in existing LED devices.

本发明一方面提供了一种LED外延片。该外延片包括：由衬底表面向外依次设置的未掺杂GaN层、N型GaN层、有源层以及P型GaN层，其中有源层包括一组或多组量子阱层，各量子阱层包括沿远离所述衬底10的方向依次设置的InGaN势阱层41、GaN势垒层43和MgN势垒层45。One aspect of the present invention provides an LED epitaxial wafer. The epitaxial wafer includes: an undoped GaN layer, an N-type GaN layer, an active layer, and a P-type GaN layer sequentially arranged from the surface of the substrate, wherein the active layer includes one or more sets of quantum well layers, and each quantum The well layer includes an InGaN potential well layer 41 , a GaN barrier layer 43 and a MgN barrier layer 45 arranged in sequence along a direction away from the substrate 10 .

进一步地，在上述LED外延片中，在有源层中包括10～13组量子阱层。Further, in the above-mentioned LED epitaxial wafer, the active layer includes 10-13 sets of quantum well layers.

进一步地，在上述LED外延片中，各组量子阱层中MgN势垒层的厚度为0.3～1.0nm。Further, in the above-mentioned LED epitaxial wafer, the thickness of the MgN barrier layer in each group of quantum well layers is 0.3-1.0 nm.

进一步地，在上述LED外延片中，InGaN势阱层的厚度为2.5～3.5nm，GaN势垒层的厚度为10～13nm，优选的，InGaN势阱层中In的掺杂浓度为2E+20～5E+20atom/cm³。Further, in the above-mentioned LED epitaxial wafer, the thickness of the InGaN potential well layer is 2.5-3.5 nm, and the thickness of the GaN barrier layer is 10-13 nm. Preferably, the doping concentration of In in the InGaN potential well layer is 2E+20 ~5E+20 atoms/cm³ .

本发明的另一方面在于提供了一种LED外延片的制作方法。该制作方法包括以下步骤：包括由衬底表面向外依次形成未掺杂GaN层、N型GaN层、有源层以及P型GaN层，其中形成有源层的步骤包括依次形成一组或多组量子阱层，形成各组量子阱层的步骤包括：由N型GaN层表面向外的方向，依次形成InGaN势阱层、GaN势垒层和MgN势垒层。Another aspect of the present invention is to provide a method for manufacturing an LED epitaxial wafer. The manufacturing method includes the following steps: including sequentially forming an undoped GaN layer, an N-type GaN layer, an active layer, and a P-type GaN layer from the surface of the substrate outward, wherein the step of forming the active layer includes sequentially forming one or more A group of quantum well layers, the steps of forming each group of quantum well layers include: sequentially forming an InGaN potential well layer, a GaN barrier layer and a MgN barrier layer from the surface of the N-type GaN layer outward.

进一步地，在上述LED外延片的制作方法中，形成有源层的步骤中依次形成10～13组量子阱层。Further, in the manufacturing method of the above-mentioned LED epitaxial wafer, in the step of forming the active layer, 10-13 groups of quantum well layers are sequentially formed.

进一步地，在上述LED外延片的制作方法中，形成MgN势垒层的步骤包括：在与生长GaN势垒层相同的温度和压力的氮气气氛下，或氢气和氮气的混合气氛下，通入镁源生长形成厚度为0.3～1.0nm的MgN势垒层。Further, in the above method of manufacturing the LED epitaxial wafer, the step of forming the MgN barrier layer includes: under the nitrogen atmosphere at the same temperature and pressure as that used for growing the GaN barrier layer, or under the mixed atmosphere of hydrogen and nitrogen, injecting The magnesium source grows to form a MgN barrier layer with a thickness of 0.3-1.0 nm.

进一步地，在上述LED外延片的制作方法中，形成InGaN势阱层和GaN势垒层的步骤包括：在温度为730～760℃，压力为150～300torr的氮气气氛下，或氢气和氮气的混合气氛下，通入镓源和铟源生长形成厚度为2.5～3.5nm，In的掺杂浓度为2E+20～5E+20atom/cm³的InGaN势阱层；停止通入铟源，升温至840～890℃，保持压力不变，生长形成厚度为10～13nm的GaN势垒层。Further, in the above-mentioned method for manufacturing an LED epitaxial wafer, the step of forming the InGaN potential well layer and the GaN barrier layer includes: under a nitrogen atmosphere with a temperature of 730-760° C. and a pressure of 150-300 torr, or in an atmosphere of hydrogen and nitrogen Under the mixed atmosphere, feed the gallium source and the indium source to grow and form an InGaN potential well layer with a thickness of 2.5-3.5nm and an In doping concentration of 2E+20-5E+20atom/^cm3 ; stop feeding the indium source, and raise the temperature to 840-890°C, keep the pressure constant, grow and form a GaN barrier layer with a thickness of 10-13nm.

进一步地，在上述LED外延片的制作方法中，在生长InGaN势阱层的步骤中，以三乙基镓或三甲基镓作为镓源，三甲基铟作为铟源；在生长GaN势垒层的步骤中，以三乙基镓或三甲基镓作为镓源；在生长MgN势垒层的步骤中，以二茂镁作为镁源。Further, in the method for making the above-mentioned LED epitaxial wafer, in the step of growing the InGaN potential well layer, triethylgallium or trimethylgallium is used as the gallium source, and trimethylindium is used as the indium source; In the step of growing the MgN barrier layer, triethylgallium or trimethylgallium is used as the gallium source; in the step of growing the MgN barrier layer, magnesocene is used as the magnesium source.

本发明的又一方面在于提供了一种LED芯片。该芯片包括衬底、设置在衬底上的外延片，以及设置在外延片上的P电极和N电极，其中外延片为本发明提供的外延片。Another aspect of the present invention is to provide an LED chip. The chip includes a substrate, an epitaxial wafer disposed on the substrate, and a P electrode and an N electrode disposed on the epitaxial wafer, wherein the epitaxial wafer is the epitaxial wafer provided by the present invention.

应用本发明的技术方案，在有源区的GaN势垒层上形成MgN势垒层，该MgN势垒层可以改善有源层的界面态和粗糙度，降低有源层中的晶格位错和缺陷，提高有源层的结晶质量，进而有效减少了有源层中的非辐射复合中心，提高了LED器件的内量子效率。在结晶质量得到有效提高的条件下，InGaN势阱层更有利于In凝聚形成In量子点，In量子点能够捕获载流子并进行辐射复合发光，也就是增加了辐射复合中心，从而提高了器件的内量子效率，并最终提高器件的发光效率。同时，该MgN势垒层在量子阱中形成循环的小型PN结，可提高空穴在量子阱中的续航能力，从而大幅度提高空穴在量子阱中的浓度，有效提高辐射复合效率，进一步提高了LED器件的内量子效率。Applying the technical scheme of the present invention, a MgN barrier layer is formed on the GaN barrier layer in the active region, and the MgN barrier layer can improve the interface state and roughness of the active layer, and reduce lattice dislocations in the active layer and defects, improve the crystalline quality of the active layer, thereby effectively reducing the non-radiative recombination center in the active layer, and improving the internal quantum efficiency of the LED device. Under the condition that the crystal quality is effectively improved, the InGaN potential well layer is more conducive to the condensation of In to form In quantum dots. In quantum dots can capture carriers and perform radiative recombination to emit light, that is, increase the radiative recombination center, thereby improving the performance of the device. internal quantum efficiency, and ultimately improve the luminous efficiency of the device. At the same time, the MgN barrier layer forms a circular small PN junction in the quantum well, which can improve the endurance of holes in the quantum well, thereby greatly increasing the concentration of holes in the quantum well, effectively improving the radiation recombination efficiency, and further The internal quantum efficiency of the LED device is improved.

附图说明Description of drawings

构成本发明的一部分的附图用来提供对本发明的进一步理解，本发明的示意性实施例及其说明用于解释本发明，并不构成对本发明的不当限定。在附图中：The drawings constituting a part of the present invention are used to provide a further understanding of the present invention, and the schematic embodiments and descriptions of the present invention are used to explain the present invention, and do not constitute an improper limitation of the present invention. In the attached picture:

图1示出了现有LED外延片的结构示意图；Fig. 1 shows the structural representation of existing LED epitaxial wafer;

图2示出了本发明实施例提供的LED外延片的结构示意图；FIG. 2 shows a schematic structural view of an LED epitaxial wafer provided by an embodiment of the present invention;

图3示出了本发明实施例提供的LED外延片的制作方法的流程示意图；FIG. 3 shows a schematic flow chart of a method for manufacturing an LED epitaxial wafer provided by an embodiment of the present invention;

图4示出了在本发明实施例提供的LED外延片的制作过程中，由衬底表面向外依次形成GaN层和N型GaN层后基体的剖面结构示意图；Fig. 4 shows a schematic cross-sectional structure diagram of the substrate after the GaN layer and the N-type GaN layer are sequentially formed outward from the substrate surface during the manufacturing process of the LED epitaxial wafer provided by the embodiment of the present invention;

图5示出了在图4中N型GaN层上形成有源层后基体的剖面结构示意图；以及FIG. 5 shows a schematic cross-sectional structure of the substrate after the active layer is formed on the N-type GaN layer in FIG. 4; and

图6示出了在图5中有源层上形成P型GaN层后基体的剖面结构示意图。FIG. 6 shows a schematic cross-sectional structure of the substrate after forming a P-type GaN layer on the active layer in FIG. 5 .

具体实施方式detailed description

下面，将参照附图更详细地描述根据本发明的示例性实施例。然而，这些示例性实施例可以由多种不同的形式来实施，并且不应当被解释为只限于这里所阐述的实施例。应当理解的是，提供这些实施例是为了使得本发明的公开彻底且完整，并且将这些示例性实施例的构思充分传达给本领域普通技术人员。但是本发明可以由权利要求限定和覆盖的多种不同方式实施。Hereinafter, exemplary embodiments according to the present invention will be described in more detail with reference to the accompanying drawings. These example embodiments may, however, be embodied in many different forms and should not be construed as limited to only the embodiments set forth herein. It should be understood that these embodiments are provided so that this disclosure will be thorough and complete and will fully convey the concept of these exemplary embodiments to those of ordinary skill in the art. But the invention can be embodied in many different ways as defined and covered by the claims.

在本发明中术语“InGaN”是指掺杂In后形成的GaN层；术语P型GaN层是指掺杂Mg或掺杂Al或同时掺杂Mg和Al后形成的GaN层；术语N型GaN层是指掺杂Si后形成的GaN层；术语AlGaN层是指同时掺杂Al和Si的GaN层。In the present invention, the term "InGaN" refers to the GaN layer formed after doping In; the term P-type GaN layer refers to the GaN layer formed after doping Mg or Al or doping Mg and Al at the same time; the term N-type GaN A layer refers to a GaN layer formed after doping Si; the term AlGaN layer refers to a GaN layer doped with Al and Si at the same time.

由背景技术可知，现有LED器件存在的有源层结晶质量差、晶格缺陷多的技术问题，本发明的发明人对上述问题进行研究，提出了一种LED外延片。如图2所示，该外延片包括由衬底10表面向外依次设置的未掺杂GaN层20、N型GaN层30、有源层40以及P型GaN层50，其中有源层40包括一组或多组量子阱层，各量子阱层包括沿远离衬底10的方向依次设置的InGaN势阱层41、GaN势垒层43和MgN势垒层45。It can be seen from the background art that existing LED devices have the technical problems of poor crystallization quality of the active layer and many lattice defects. The inventors of the present invention studied the above problems and proposed an LED epitaxial wafer. As shown in FIG. 2, the epitaxial wafer includes an undoped GaN layer 20, an N-type GaN layer 30, an active layer 40, and a P-type GaN layer 50, which are sequentially arranged outward from the surface of the substrate 10, wherein the active layer 40 includes One or more sets of quantum well layers, each quantum well layer includes an InGaN potential well layer 41 , a GaN barrier layer 43 and a MgN barrier layer 45 arranged in sequence along a direction away from the substrate 10 .

本发明所保护的上述LED外延片中有源层40可以是一层，也可以是根据需要重复设置的多层。在本发明的一种优选的实施方式中，该有源层40中包括10～13组量子阱层。The active layer 40 in the above-mentioned LED epitaxial wafer protected by the present invention can be one layer, or multiple layers that are repeatedly arranged as required. In a preferred embodiment of the present invention, the active layer 40 includes 10-13 groups of quantum well layers.

在本发明所提供的LED外延片中，在有源层40的GaN势垒层43上形成了MgN势垒层45。该MgN势垒层45可以改善有源层40的界面态和粗糙度，降低有源层40中的晶格缺陷，提高有源层40的结晶质量，有效减少非辐射复合中心，从而提高LED器件的内量子效率。在结晶质量得到有效提高的条件下，InGaN势阱层更有利于In凝聚形成In量子点，In量子点能够捕获载流子并进行辐射复合发光，也就是增加了辐射复合中心，从而提高了器件的内量子效率，并最终提高器件的发光效率。同时，该MgN势垒层在量子阱中形成循环的小型PN结，可提高空穴在量子阱中的续航能力，从而大幅度提高空穴在量子阱中的浓度，有效提高辐射复合效率，进一步提高了LED器件的内量子效率和发光效率。In the LED epitaxial wafer provided by the present invention, a MgN barrier layer 45 is formed on the GaN barrier layer 43 of the active layer 40 . The MgN barrier layer 45 can improve the interface state and roughness of the active layer 40, reduce the lattice defects in the active layer 40, improve the crystal quality of the active layer 40, effectively reduce the non-radiative recombination center, thereby improving the LED device. internal quantum efficiency. Under the condition that the crystal quality is effectively improved, the InGaN potential well layer is more conducive to the condensation of In to form In quantum dots. In quantum dots can capture carriers and perform radiative recombination to emit light, that is, increase the radiative recombination center, thereby improving the performance of the device. internal quantum efficiency, and ultimately improve the luminous efficiency of the device. At the same time, the MgN barrier layer forms a circular small PN junction in the quantum well, which can improve the endurance of holes in the quantum well, thereby greatly increasing the concentration of holes in the quantum well, effectively improving the radiation recombination efficiency, and further The internal quantum efficiency and luminous efficiency of the LED device are improved.

在本发明所提供的LED外延片中，各组量子阱层中MgN势垒层45厚度可以是任意的，但优选该MgN势垒层45的厚度为0.3～1.0nm。该MgN势垒层45不易过厚，不然会使外延片表面粗化，不利于后段工艺。如果Mg在量子阱中含量过多，会导致MgGaN的能级出现，产生过多的无效辐射复合中心；同时会影响结晶质量，致使电性不好。In the LED epitaxial wafer provided by the present invention, the thickness of the MgN barrier layer 45 in each group of quantum well layers can be arbitrary, but the thickness of the MgN barrier layer 45 is preferably 0.3-1.0 nm. The MgN barrier layer 45 is not easy to be too thick, otherwise the surface of the epitaxial wafer will be roughened, which is not conducive to the subsequent process. If the content of Mg in the quantum well is too much, it will cause the energy level of MgGaN to appear, resulting in too many invalid radiation recombination centers; at the same time, it will affect the crystal quality, resulting in poor electrical properties.

在本发明所提供的LED外延片中，GaN势垒层43和InGaN势阱层41的厚度可以参照现有技术对其的要求进行设定，更为优选地，GaN势垒层43的厚度为10～13nm，InGaN势阱层41的厚度为2.5～3.5nm。更优选地，在上述InGaN势阱层41，In的掺杂浓度为2E+20～3E+20atom/cm³。InGaN势阱层41的厚度控制在2.5～3.5nm，以保证器件因极化电场作用而致使能带弯曲在可接受范围内，有效控制波长半波宽和蓝移。In the LED epitaxial wafer provided by the present invention, the thicknesses of the GaN barrier layer 43 and the InGaN potential well layer 41 can be set with reference to the requirements of the prior art. More preferably, the thickness of the GaN barrier layer 43 is 10-13 nm, and the thickness of the InGaN potential well layer 41 is 2.5-3.5 nm. More preferably, in the above-mentioned InGaN potential well layer 41 , the doping concentration of In is 2E+20˜3E+20 atom/cm³ . The thickness of the InGaN potential well layer 41 is controlled at 2.5-3.5 nm to ensure that the energy band bending of the device due to the action of the polarization electric field is within an acceptable range, effectively controlling the half-wavelength width and blue shift.

同时，本发明还提供了一种LED外延片的制作方法。图3示出了本发明提供的LED外延片的制作方法的流程示意图。如图3所示，这种LED外延片的制作方法包括由衬底10表面向外依次形成未掺杂GaN层20、N型GaN层30、有源层40以及P型GaN层50，其中形成有源层40的步骤包括：依次形成一组或多组量子阱层，形成各量子势垒层的步骤包括：由N型GaN层30表面向外的方向，依次形成InGaN势阱层41、GaN势垒层43和MgN势垒层45。At the same time, the invention also provides a manufacturing method of the LED epitaxial wafer. Fig. 3 shows a schematic flowchart of the method for manufacturing an LED epitaxial wafer provided by the present invention. As shown in FIG. 3 , the manufacturing method of this LED epitaxial wafer includes sequentially forming an undoped GaN layer 20 , an N-type GaN layer 30 , an active layer 40 and a P-type GaN layer 50 from the surface of a substrate 10 to the outside. The steps of the active layer 40 include: sequentially forming one or more sets of quantum well layers, and the steps of forming each quantum barrier layer include: sequentially forming the InGaN potential well layer 41, GaN barrier layer 43 and MgN barrier layer 45 .

图4至6示出了本发明提供的LED外延片的制作方法中经过每一步骤后的剖面结构示意图。为了进一步说明本发明所提供的LED外延片的制作方法，下面将结合图4至6进一步阐述该制作方法。4 to 6 show the schematic cross-sectional structure after each step in the manufacturing method of the LED epitaxial wafer provided by the present invention. In order to further illustrate the manufacturing method of the LED epitaxial wafer provided by the present invention, the manufacturing method will be further described below in conjunction with FIGS. 4 to 6 .

首先，由衬底10表面向外依次形成未掺杂GaN层20和N型GaN层30。在本发明的一种优选实施方式中，未掺杂GaN层20包括GaN缓冲层21和GaN层23，N型GaN层30包括掺杂Al和Si的N型GaN层31和掺杂Si的N型GaN层33。此时，所形成的基体具有如图4中所示出的结构。此时，由衬底10表面向外依次形成未掺杂GaN层20和N型GaN层30包括以下步骤：First, an undoped GaN layer 20 and an N-type GaN layer 30 are sequentially formed from the surface of the substrate 10 outward. In a preferred embodiment of the present invention, the undoped GaN layer 20 includes a GaN buffer layer 21 and a GaN layer 23, and the N-type GaN layer 30 includes an N-type GaN layer 31 doped with Al and Si and a N-type layer doped with Si. type GaN layer 33 . At this time, the formed base has a structure as shown in FIG. 4 . At this time, sequentially forming the undoped GaN layer 20 and the N-type GaN layer 30 from the surface of the substrate 10 includes the following steps:

从室温升温至1000～1100℃，在反应室压力为400～600mbar的氢气气氛下处理衬底105～10分钟。The temperature is raised from room temperature to 1000-1100° C., and the substrate is processed for 105-10 minutes in a hydrogen atmosphere with a pressure of 400-600 mbar in the reaction chamber.

降温至530～580℃，在反应室压力为450～550torr的氢气和氮气混合气氛下，对衬底10进行氮化处理，处理时间为2～6分钟；然后通入镓源，在衬底10上生长厚度为30～40nm的GaN缓冲层21。优选地，镓源包括但不限于三乙基镓或三甲基镓，氢气和氮气混合气氛中氢气的体积分数为10%～20%。Lower the temperature to 530-580° C., and carry out nitriding treatment on the substrate 10 in a reaction chamber pressure of 450-550 torr in a mixed atmosphere of hydrogen and nitrogen. The treatment time is 2-6 minutes; A GaN buffer layer 21 with a thickness of 30-40 nm is grown thereon. Preferably, the gallium source includes but not limited to triethylgallium or trimethylgallium, and the volume fraction of hydrogen in the mixed atmosphere of hydrogen and nitrogen is 10%-20%.

升温至1050～1250℃，在压力为100～250torr的氢气、氮气混合气氛下，持续通入镓源生长厚度为2.5～3.5um的未掺杂GaN层23。The temperature is raised to 1050-1250° C., and the undoped GaN layer 23 with a thickness of 2.5-3.5 um is grown by continuously injecting a gallium source under a mixed atmosphere of hydrogen and nitrogen at a pressure of 100-250 torr.

在温度为900～1100℃，反应室压力为50～200torr的氮气气氛或氢气和氮气混合气氛下，持续通入镓源、并相应通入铝源和硅源，生长厚度为40～60nm的N型AlGaN层31，其中Al的掺杂浓度为1E+20～4E+20atom/cm³，Si的掺杂浓度为5E+17～9E+17atom/cm³。优选地，铝源优选包括但不限于三甲基铝，硅源优选包括但不限于硅烷。In a nitrogen atmosphere or a mixed atmosphere of hydrogen and nitrogen at a temperature of 900-1100°C and a reaction chamber pressure of 50-200 torr, the gallium source is continuously introduced, and the aluminum source and silicon source are respectively introduced to grow N with a thickness of 40-60nm. Type AlGaN layer 31 , wherein the doping concentration of Al is 1E+20˜4E+20 atom/cm³ , and the doping concentration of Si is 5E+17˜9E+17 atom/cm³ . Preferably, the aluminum source preferably includes but not limited to trimethylaluminum, and the silicon source preferably includes but not limited to silane.

在温度为1050～1250℃，反应室压力为100～250torr的氢气和氮气混合气氛下，持续通入镓源和和硅源，停止通入铝源，生长厚度为3.0～3.5um的N型GaN层33，其中Si的掺杂浓度为4E+18～8E+18atom/cm³。In a mixed atmosphere of hydrogen and nitrogen at a temperature of 1050-1250°C and a reaction chamber pressure of 100-250 torr, the gallium source and the silicon source are continuously introduced, and the aluminum source is stopped to grow N-type GaN with a thickness of 3.0-3.5um. Layer 33, wherein the doping concentration of Si is 4E+18-8E+18 atom/cm³ .

在完成由衬底10表面向外依次形成未掺杂GaN层20和N型GaN层30的步骤之后，在N型GaN层30上形成有源层40，其中形成有源层40的步骤包括依次形成一组或多组量子阱层，其中形成各量子势垒层的步骤包括由N型GaN层30表面向外的方向，依次形成InGaN势阱层41、GaN势垒层43和MgN势垒层45。此时，所形成的基体具有如图5中所示出的结构。After completing the step of sequentially forming the undoped GaN layer 20 and the N-type GaN layer 30 outward from the surface of the substrate 10, an active layer 40 is formed on the N-type GaN layer 30, wherein the step of forming the active layer 40 includes sequentially Forming one or more groups of quantum well layers, wherein the step of forming each quantum barrier layer includes sequentially forming an InGaN potential well layer 41, a GaN barrier layer 43 and a MgN barrier layer from the surface of the N-type GaN layer 30 to the outside 45. At this time, the formed base has a structure as shown in FIG. 5 .

在本发明的一种优选实施方式中，在形成有源层40的步骤中依次形成1层、5层、10层、11层、12层、13层或15层量子阱层，其中优选形成10～13组量子阱层，形成每组量子阱层中InGaN势阱层41、GaN势垒层43和MgN势垒层45的步骤包括：In a preferred embodiment of the present invention, in the step of forming the active layer 40, 1 layer, 5 layers, 10 layers, 11 layers, 12 layers, 13 layers or 15 quantum well layers are sequentially formed, wherein preferably 10 layers are formed. ~13 groups of quantum well layers, the steps of forming the InGaN potential well layer 41, the GaN barrier layer 43 and the MgN barrier layer 45 in each group of quantum well layers include:

（1）在温度为730～760℃，压力为150～300torr的氮气，或氢气和氮气的混合气氛下，通入镓源和铟源生长厚度为2.5～3.5nm，In的掺杂浓度为2E+20～5E+20atom/cm³的InGaN势阱层41，其中，氢气和氮气混合气氛中氢气的体积分数为10%～20%，镓源优选包括但不限于三乙基镓或三甲基镓，铟源优选包括但不限于三甲基铟。(1) Under nitrogen gas at a temperature of 730-760°C and a pressure of 150-300 torr, or a mixed atmosphere of hydrogen and nitrogen, feed gallium source and indium source to grow with a thickness of 2.5-3.5nm, and the doping concentration of In is 2E InGaN potential well layer 41 of +20～5E+20atom/cm³ , wherein the volume fraction of hydrogen in the mixed atmosphere of hydrogen and nitrogen is 10%～20%, and the source of gallium preferably includes but not limited to triethylgallium or trimethyl Gallium, indium sources preferably include but are not limited to trimethylindium.

（2）在步骤（1）的基础上停止通入铟源，持续通入镓源，升温至840～890℃，保持压力不变，生长厚度为10～13nm的GaN势垒层43；其中，镓源的原料以及通入方式与步骤（1）中相同。(2) On the basis of step (1), stop feeding the indium source, continue feeding the gallium source, raise the temperature to 840-890°C, keep the pressure constant, and grow a GaN barrier layer 43 with a thickness of 10-13nm; wherein, The raw materials and feeding method of the gallium source are the same as in step (1).

（3）在步骤（2）的基础上停止通入镓源，保持温度和压力不变，通入镁源生长厚度为0.3～1.0nm的MgN势垒层45。其中，镁源优选包括但不限于二茂镁生长。(3) Stop feeding the gallium source on the basis of step (2), keep the temperature and pressure constant, feed the magnesium source to grow the MgN barrier layer 45 with a thickness of 0.3-1.0 nm. Among them, the magnesium source preferably includes but not limited to the growth of magnesiumocene.

在该步骤中，通过采用相同的温度和压力生长MgN势垒层45和GaN势垒层43，能够得到结晶质量较好的MgN薄层，相反生长条件的频繁改变会对GaN的结晶产生不利影响。In this step, by using the same temperature and pressure to grow the MgN barrier layer 45 and the GaN barrier layer 43, a thin MgN layer with better crystalline quality can be obtained. On the contrary, frequent changes in growth conditions will have an adverse effect on the crystallization of GaN. .

在完成在N型GaN层30上形成有源层40的步骤之后，在有源层40上形成P型GaN层50。该P型GaN层50可以根据后续使用要求依据现有技术进行合理调整，在本发明的一种优选实施方式中，P型GaN层50包括掺杂Al和Mg的P型AlGaN层51、掺杂Mg的P型GaN层53以及P型GaN接触层55。此时，所形成的基体具有如图6中所示出的结构。在一种优选方案中，在有源层40上形成P型GaN层50包括以下步骤：After the step of forming the active layer 40 on the N-type GaN layer 30 is completed, the P-type GaN layer 50 is formed on the active layer 40 . The P-type GaN layer 50 can be reasonably adjusted according to the existing technology according to subsequent use requirements. In a preferred embodiment of the present invention, the P-type GaN layer 50 includes a P-type AlGaN layer 51 doped with Al and Mg, doped Mg P-type GaN layer 53 and P-type GaN contact layer 55 . At this time, the formed base has a structure as shown in FIG. 6 . In a preferred solution, forming the p-type GaN layer 50 on the active layer 40 includes the following steps:

升温至850～1050℃，在反应室压力为50～200torr的氮气气氛，或氢气和氮气混合气氛下，通入镓源、铝源和镁源，生长厚度为30～60nm的p型AlGaN层51，其中Al的掺杂浓度为1E+20～4E+20atom/cm³，Mg掺杂浓度为9E+18～2E+19atom/cm³。优选地，镓源包括但不限于三乙基镓或三甲基镓，铝源包括但不限于三甲基铝，镁源包括但不限于二茂镁。Raise the temperature to 850-1050°C, in a nitrogen atmosphere with a pressure of 50-200 torr, or a mixed atmosphere of hydrogen and nitrogen, feed gallium source, aluminum source and magnesium source, and grow a p-type AlGaN layer 51 with a thickness of 30-60nm , wherein the doping concentration of Al is 1E+20˜4E+20 atom/cm³ , and the doping concentration of Mg is 9E+18˜2E+19 atom/cm³ . Preferably, the gallium source includes but not limited to triethylgallium or trimethylgallium, the aluminum source includes but not limited to trimethylaluminum, and the magnesium source includes but not limited to magnesiumocene.

在温度为850～1000℃，反应室压力为100～250torr的氢气和氮气混合气氛下，通入镓源和镁源生长厚度为70～100nm的P型GaN层53，其中Mg的掺杂浓度为5E+19～2E+20atom/cm³。优选地，镓源包括但不限于三乙基镓或三甲基镓，镁源包括但不限于二茂镁。In a mixed atmosphere of hydrogen and nitrogen at a temperature of 850-1000° C. and a reaction chamber pressure of 100-250 torr, a gallium source and a magnesium source are introduced to grow a P-type GaN layer 53 with a thickness of 70-100 nm, wherein the doping concentration of Mg is 5E+19～2E+20atom/cm³ . Preferably, the gallium source includes but not limited to triethylgallium or trimethylgallium, and the magnesium source includes but not limited to magnesiumocene.

保持温度、气氛和压力不变，通入镓源和镁源，生长厚度为2～4nm的p型GaN型接触层55，其中Mg的掺杂浓度为4E+20～9E+20atom/cm³。优选地，镓源包括但不限于三乙基镓或三甲基镓，镁源包括但不限于二茂镁。Keeping the temperature, atmosphere and pressure constant, feed gallium source and magnesium source to grow a p-type GaN contact layer 55 with a thickness of 2-4nm, wherein the doping concentration of Mg is 4E+20-9E+20atom/cm³ . Preferably, the gallium source includes but not limited to triethylgallium or trimethylgallium, and the magnesium source includes but not limited to magnesiumocene.

降温至670～730℃，在压力为50～200torr的氮气气氛下，保温5～20min；然后，随炉冷却至室温，即得到LED外延片。Lower the temperature to 670-730° C., and keep it warm for 5-20 minutes under a nitrogen atmosphere with a pressure of 50-200 torr; then, cool down to room temperature with the furnace to obtain an LED epitaxial wafer.

上述生长工艺可以包括但不限于采用化学气相沉积、溅射、热沉积，上述工艺为本领域常见的技术手段，在此不再赘述。The above-mentioned growth process may include but not limited to chemical vapor deposition, sputtering, and thermal deposition. The above-mentioned processes are common technical means in the field and will not be repeated here.

本发明还提供了一种LED芯片，包括衬底10、设置在衬底10上的外延片，以及设置在外延片上的P电极和N电极。其中，外延片为本发明提供的外延片。The present invention also provides an LED chip, comprising a substrate 10, an epitaxial wafer disposed on the substrate 10, and a P electrode and an N electrode disposed on the epitaxial wafer. Wherein, the epitaxial wafer is the epitaxial wafer provided by the present invention.

以下将以具体实施例进一步说明本发明所提供的LED的制作方法。The manufacturing method of the LED provided by the present invention will be further described below with specific examples.

实施例1Example 1

本实施例提供了一种LED外延片的制作方法，包括以下步骤：This embodiment provides a method for manufacturing an LED epitaxial wafer, comprising the following steps:

首先，由衬底表面向外依次形成GaN缓冲层、GaN层、N型AlGaN和掺杂Si的N型GaN，包括以下步骤：First, a GaN buffer layer, GaN layer, N-type AlGaN, and Si-doped N-type GaN are sequentially formed from the surface of the substrate outward, including the following steps:

从室温升温至1100℃，在反应室压力为500mbar的氢气气氛下处理衬底10分钟；Raise the temperature from room temperature to 1100°C, and process the substrate for 10 minutes under a hydrogen atmosphere with a pressure of 500mbar in the reaction chamber;

降温至580℃，在反应室压力为500torr的氢气和氮气的混合气氛下，对衬底进行氮化处理，处理时间为5分钟，其中混合气氛中氢气的体积分数为10%；然后通入三乙基镓或三甲基镓，在衬底上生长厚度为540nm的GaN缓冲层；The temperature was lowered to 580°C, and the substrate was nitrided in a mixed atmosphere of hydrogen and nitrogen at a pressure of 500 torr in the reaction chamber. The treatment time was 5 minutes, and the volume fraction of hydrogen in the mixed atmosphere was 10%; Ethylgallium or trimethylgallium, a GaN buffer layer with a thickness of 540nm is grown on the substrate;

升温至1200℃，在压力为200torr的氢气和氮气的混合气氛下，通入三甲基镓生长厚度为3um的非掺杂GaN层；Raise the temperature to 1200°C, and in a mixed atmosphere of hydrogen and nitrogen at a pressure of 200torr, pass through trimethylgallium to grow a non-doped GaN layer with a thickness of 3um;

在温度为1000℃，反应室压力为200torr的氢气和氮气的混合气氛下，通入三甲基镓、三甲基铝和硅烷，生长厚度为50nm，Al的掺杂浓度为4E+20atom/cm³，Si的掺杂浓度6E+17为atom/cm³的N型AlGaN层，其中混合气氛中氢气的体积分数为10%；In a mixed atmosphere of hydrogen and nitrogen at a temperature of 1000°C and a reaction chamber pressure of 200 torr, trimethylgallium, trimethylaluminum and silane are introduced, the growth thickness is 50nm, and the doping concentration of Al is 4E+20atom/cm^3. An N-type AlGaN layer with a Si doping concentration of 6E+17 atom/cm³ , where the volume fraction of hydrogen in the mixed atmosphere is 10%;

在温度为1200℃，反应室压力为200torr的氢气和氮气的混合气氛下，通入三甲基镓，以及硅烷，生长厚度为3.0um，Si的掺杂浓度为6E+18atom/cm³的N型GaN层，其中混合气氛中氢气的体积分数为10%。In a mixed atmosphere of hydrogen and nitrogen at a temperature of 1200°C and a reaction chamber pressure of 200torr, trimethylgallium and silane are introduced to grow a thickness of 3.0um, and the doping concentration of Si is 6E+18atom/cm³ N Type GaN layer, wherein the volume fraction of hydrogen in the mixed atmosphere is 10%.

然后，在N型GaN层上依次形成11组量子阱层，形成每组量子阱层包括以下步骤：Then, 11 groups of quantum well layers are sequentially formed on the N-type GaN layer, and forming each group of quantum well layers includes the following steps:

在温度为750℃，压力为200torr的氢气和氮气的混合气氛下，通入三甲基镓和三甲基铟生长厚度为3nm，In的掺杂浓度为2E+20atom/cm³的InGaN势阱层，其中混合气氛中氢气的体积分数为10%；In a mixed atmosphere of hydrogen and nitrogen at a temperature of 750°C and a pressure of 200 torr, inject trimethylgallium and trimethylindium to grow an InGaN potential well with a thickness of 3nm and an In doping concentration of 2E+20atom/cm³ layer, wherein the volume fraction of hydrogen in the mixed atmosphere is 10%;

停止通入三甲基铟，升温至860℃，保持压力不变，生长厚度为11nm的GaN势垒层；停止通入三甲基镓，保持温度和压力不变，通入二茂镁生长厚度为0.7nm的MgN势垒层。Stop feeding trimethyl indium, raise the temperature to 860°C, keep the pressure constant, and grow a GaN barrier layer with a thickness of 11nm; stop feeding trimethyl gallium, keep the temperature and pressure constant, and feed dimagnesium to grow a thickness 0.7nm MgN barrier layer.

最后，在有源层上形成P型AlGaN层、掺杂Mg的P型GaN层以及P型GaN接触层，包括以下步骤：Finally, forming a P-type AlGaN layer, a Mg-doped P-type GaN layer and a P-type GaN contact layer on the active layer includes the following steps:

升温至1000℃，在反应室压力为150torr的氢气和氮气的混合气氛下，通入三甲基镓、三甲基铝和二茂镁，生长厚度为50nm的p型AlGaN层，其中Al的掺杂浓度为2E+20atom/cm³，Mg掺杂浓度为2E+19atom/cm³，其中混合气氛中氢气的体积分数为10%。Raise the temperature to 1000°C, under the mixed atmosphere of hydrogen and nitrogen at the pressure of 150torr in the reaction chamber, feed trimethylgallium, trimethylaluminum and dichloromagnesium to grow a p-type AlGaN layer with a thickness of 50nm, in which Al doped The impurity concentration is 2E+20atom/cm³ , the Mg doping concentration is 2E+19atom/cm³ , and the volume fraction of hydrogen in the mixed atmosphere is 10%.

在温度为900℃，反应室压力为200torr的氢气和氮气的混合气氛下，通入三甲基镓和二茂镁，生长厚度为80nm，Mg掺杂浓度为8E+19atom/cm³的P型GaN层，其中混合气氛中氢气的体积分数为10%。In a mixed atmosphere of hydrogen and nitrogen at a temperature of 900°C and a pressure of 200 torr in the reaction chamber, trimethylgallium and dimagnesium were introduced to grow a P-type with a thickness of 80nm and a Mg doping concentration of 8E+19atom/cm³ GaN layer, wherein the volume fraction of hydrogen in the mixed atmosphere is 10%.

保持温度、压力不变，通入三甲基镓和二茂镁，生长厚度为3nm的p型GaN型接触层，其中Mg掺杂浓度为5E+20atom/cm³。Keeping the temperature and pressure constant, injecting trimethylgallium and magnesocene to grow a p-type GaN contact layer with a thickness of 3nm, wherein the Mg doping concentration is 5E+20atom/cm³ .

降温至700℃，在压力为150torr的氮气气氛下，保温15min；然后，随炉冷却至室温，即得到LED外延片。Lower the temperature to 700° C., and keep it warm for 15 minutes under a nitrogen atmosphere with a pressure of 150 torr; then, cool down to room temperature with the furnace to obtain an LED epitaxial wafer.

实施例2Example 2

本实施例提供了一种LED外延片的制作方法，其中由衬底表面向外依次形成GaN缓冲层21、GaN层23、N型AlGaN和掺杂Si的N型GaN的步骤，以及在有源层上形成P型AlGaN层、掺杂Mg的P型GaN层以及P型GaN接触层的步骤与实施例1相同。This embodiment provides a method for manufacturing an LED epitaxial wafer, wherein the steps of sequentially forming a GaN buffer layer 21, a GaN layer 23, an N-type AlGaN, and a Si-doped N-type GaN from the surface of the substrate outward, and The steps of forming a P-type AlGaN layer, a Mg-doped P-type GaN layer and a P-type GaN contact layer on the layer are the same as those in Embodiment 1.

在本实施例中，在N型GaN层上形成有源层的步骤：依次形成10组量子阱层，形成每组量子阱层包括以下步骤：In this embodiment, the step of forming the active layer on the N-type GaN layer: sequentially forming 10 groups of quantum well layers, forming each group of quantum well layers includes the following steps:

在温度为730℃，压力为300torr的氮气气氛下，通入三甲基镓，以及三甲基铟生长厚度为2.5nm，In的掺杂浓度为3E+20atom/cm³的InGaN势阱层；In a nitrogen atmosphere at a temperature of 730°C and a pressure of 300torr, trimethylgallium and trimethylindium are introduced into an InGaN potential well layer with a thickness of 2.5nm and an In doping concentration of 3E+20atom/cm³ ;

停止通入三甲基铟，升温至840℃，保持压力不变，生长厚度为13nm的GaN势垒层；停止通入三甲基镓，保持温度和压力不变，通入二茂镁生长厚度为0.3nm的MgN势垒层。Stop feeding trimethyl indium, raise the temperature to 840°C, keep the pressure constant, and grow a GaN barrier layer with a thickness of 13nm; stop feeding trimethyl gallium, keep the temperature and pressure constant, and feed dimagnesocene to grow a thickness 0.3nm MgN barrier layer.

实施例3Example 3

本实施例提供了一种LED外延片的制作方法，其中由衬底表面向外依次形成GaN缓冲层、GaN层、N型AlGaN和掺杂Si的N型GaN的步骤，以及在有源层上形成P型AlGaN层、掺杂Mg的P型GaN层以及P型GaN接触层的步骤与实施例1相同。This embodiment provides a method for manufacturing an LED epitaxial wafer, wherein the steps of sequentially forming a GaN buffer layer, a GaN layer, N-type AlGaN, and Si-doped N-type GaN from the surface of the substrate outward, and on the active layer The steps of forming the P-type AlGaN layer, the Mg-doped P-type GaN layer and the P-type GaN contact layer are the same as those in Embodiment 1.

在本实施例中，在N型GaN层上形成有源层的步骤：依次形成13组量子阱层，形成每组量子阱层包括以下步骤：In this embodiment, the step of forming the active layer on the N-type GaN layer: sequentially forming 13 groups of quantum well layers, forming each group of quantum well layers includes the following steps:

在温度为760℃，压力为150torr的氢气和氮气的混合气氛下，通入三乙基镓和三甲基铟生长厚度为3.5nm，In的掺杂浓度为5E+20atom/cm³的InGaN势阱层，其中混合气氛中氢气的体积分数为15%；In a mixed atmosphere of hydrogen and nitrogen at a temperature of 760°C and a pressure of 150 torr, triethylgallium and trimethylindium are introduced to grow InGaN with a thickness of 3.5nm and an In doping concentration of 5E+20atom/cm³ Well layer, wherein the volume fraction of hydrogen in the mixed atmosphere is 15%;

停止通入三甲基铟，升温至890℃，保持压力不变，生长厚度为10nm的GaN势垒层；停止通入三乙基镓或三甲基镓，保持温度和压力不变，通入二茂镁生长厚度为1.0nm的MgN势垒层。Stop feeding trimethylindium, raise the temperature to 890°C, keep the pressure constant, and grow a GaN barrier layer with a thickness of 10nm; stop feeding triethylgallium or trimethylgallium, keep the temperature and pressure constant, and feed A MgN barrier layer with a thickness of 1.0nm was grown on dichloromagnesium.

实施例4Example 4

本实施例提供了一种LED外延片的制作方法，其中由衬底表面向外依次形成GaN缓冲层、GaN层、N型AlGaN和掺杂Si的N型GaN的步骤，以及在有源层上形成P型AlGaN层、掺杂Mg的P型GaN层以及P型GaN接触层的步骤与实施例1相同。This embodiment provides a method for manufacturing an LED epitaxial wafer, wherein the steps of sequentially forming a GaN buffer layer, a GaN layer, N-type AlGaN, and Si-doped N-type GaN from the surface of the substrate outward, and on the active layer The steps of forming the P-type AlGaN layer, the Mg-doped P-type GaN layer and the P-type GaN contact layer are the same as those in Embodiment 1.

在本实施例中，在N型GaN层上形成有源层的步骤：依次形成15组量子阱层，形成每组量子阱层包括以下步骤：In this embodiment, the step of forming the active layer on the N-type GaN layer: sequentially forming 15 groups of quantum well layers, forming each group of quantum well layers includes the following steps:

在温度为720℃，压力为320torr的氢气和氮气的混合气氛下，通入三甲基镓和三甲基铟生长厚度为4nm，In的掺杂浓度为5.2E+20atom/cm³的InGaN势阱层，其中混合气氛中氢气的体积分数为20%；In a mixed atmosphere of hydrogen and nitrogen at a temperature of 720°C and a pressure of 320torr, trimethylgallium and trimethylindium are introduced to grow an InGaN potential with a thickness of 4nm and an In doping concentration of 5.2E+20atom/cm³ Well layer, wherein the volume fraction of hydrogen in the mixed atmosphere is 20%;

停止通入三甲基铟，升温至900℃，保持压力不变，生长厚度为15nm的GaN势垒层；停止通入三甲基镓，保持温度和压力不变，通入二茂镁生长厚度为1.5nm的MgN势垒层。Stop feeding trimethyl indium, raise the temperature to 900°C, keep the pressure constant, and grow a GaN barrier layer with a thickness of 15nm; stop feeding trimethyl gallium, keep the temperature and pressure constant, and feed dimagnesocene to grow a thickness 1.5nm MgN barrier layer.

对比例1Comparative example 1

本对比例提供了一种现有LED外延片的制作方法，其中由衬底表面向外依次形成GaN缓冲层、GaN层、N型AlGaN和掺杂Si的N型GaN的步骤，以及在有源层上形成P型AlGaN层、掺杂Mg的P型GaN层以及P型GaN接触层的步骤与实施例1相同。This comparative example provides a manufacturing method of an existing LED epitaxial wafer, wherein the steps of sequentially forming a GaN buffer layer, a GaN layer, N-type AlGaN, and Si-doped N-type GaN from the surface of the substrate outward, and The steps of forming a P-type AlGaN layer, a Mg-doped P-type GaN layer and a P-type GaN contact layer on the layer are the same as those in Embodiment 1.

在本实施例中，在N型GaN层上形成有源层的步骤：依次形成11组量子阱层，形成每组量子阱层包括以下步骤：In this embodiment, the step of forming the active layer on the N-type GaN layer: sequentially forming 11 groups of quantum well layers, forming each group of quantum well layers includes the following steps:

在温度为750℃，压力为200torr的氮气气氛下，通入三甲基镓和三甲基铟生长厚度为3nm，In的掺杂浓度为2E+20atom/cm³的InGaN势阱层；In a nitrogen atmosphere at a temperature of 750°C and a pressure of 200torr, inject trimethylgallium and trimethylindium to grow an InGaN potential well layer with a thickness of 3nm and an In doping concentration of 2E+20atom/cm³ ;

停止通入三甲基铟，升温至860℃，保持压力不变，生长厚度为11nm的GaN势垒层。The feeding of trimethylindium was stopped, the temperature was raised to 860° C., and the pressure was kept constant to grow a GaN barrier layer with a thickness of 11 nm.

测试：test:

将实施例1至4和对比例1所制得LED的5个样品，在相同的前工艺条件下镀ITO层100nm，相同的条件下镀Cr/Pt/Au电极70nm，相同的条件下镀保护层SiO2约30nm，然后在相同的条件下将样品研磨切割成762μm*762μm(30mi*30mil)的芯片颗粒，然后在实施例1至4和对比例1样品的相同位置各自挑选150颗晶粒，在相同的封装工艺下，封装成白光LED。然后采用积分球在驱动电流350mA条件下测试其亮度，并统计得出平均亮度，测试结果请见表1；测量实施例1至4和对比例1所制得LED的输出光功率随电流的变化关系，在外量子效率极值附近通过非线性拟合得到内量子效率数值，测试结果请见表1。5 samples of LEDs prepared in Examples 1 to 4 and Comparative Example 1 were plated with an ITO layer of 100 nm under the same pre-process conditions, plated with a Cr/Pt/Au electrode of 70 nm under the same conditions, and plated a protective film under the same conditions. The layer SiO2 is about 30nm, and then the sample is ground and cut into chip particles of 762 μm*762 μm (30mi*30mil) under the same conditions, and then 150 crystal grains are respectively selected at the same positions of the samples of Examples 1 to 4 and Comparative Example 1, Under the same packaging process, it is packaged into a white light LED. Then use an integrating sphere to test its brightness under the condition of a driving current of 350mA, and obtain the average brightness by statistics. The test results are shown in Table 1; the output light power of the LEDs prepared in Examples 1 to 4 and Comparative Example 1 is measured as a function of the current. The internal quantum efficiency value is obtained by nonlinear fitting near the extreme value of the external quantum efficiency. The test results are shown in Table 1.

表1Table 1

平均亮度/mwAverage brightness/mw内量子效率/%Internal quantum efficiency/%实施例1Example 13583586666

实施例2Example 23563566868实施例3Example 33603606767实施例4Example 43503506565对比例1Comparative example 13143146161

从表1可以看出，与对比例1所制得LED相比，本发明实施例1至4所制得LED的平均亮度提高了36～46mw，内量子效率提高了4%～7%。It can be seen from Table 1 that compared with the LED produced in Comparative Example 1, the average brightness of the LED produced in Examples 1 to 4 of the present invention is increased by 36-46mw, and the internal quantum efficiency is increased by 4%-7%.

从以上实施例可以看出，本发明上述的实例实现了如下技术效果：在有源区的GaN势垒层上形成MgN势垒层，该MgN势垒层可以改善有源层的界面态和粗糙度，降低有源层中的晶格位错和缺陷，提高有源层的结晶质量，进而有效减少了有源层中的非辐射复合中心。同时，该MgN势垒层在量子阱中形成循环的小型PN结，可提高空穴在量子阱中的续航能力，从而大幅度提高空穴在量子阱中的浓度，有效提高辐射复合效率，进一步提高了LED器件的内量子效率。在结晶质量得到有效提高的条件下，InGaN势阱层更有利于In凝聚形成In量子点，In量子点能够捕获载流子并进行辐射复合发光，也就是增加了辐射复合中心，从而提高了器件的内量子效率，并最终提高器件的发光效率。采用本发明提供的LED外延片的制作方法所得到LED的亮度和内量子效率得到提升。As can be seen from the above embodiments, the above-mentioned examples of the present invention have achieved the following technical effects: a MgN barrier layer is formed on the GaN barrier layer in the active region, and the MgN barrier layer can improve the interface state and roughness of the active layer. degree, reduce lattice dislocations and defects in the active layer, improve the crystal quality of the active layer, and effectively reduce the non-radiative recombination centers in the active layer. At the same time, the MgN barrier layer forms a circular small PN junction in the quantum well, which can improve the endurance of holes in the quantum well, thereby greatly increasing the concentration of holes in the quantum well, effectively improving the radiation recombination efficiency, and further The internal quantum efficiency of the LED device is improved. Under the condition that the crystal quality is effectively improved, the InGaN potential well layer is more conducive to the condensation of In to form In quantum dots. In quantum dots can capture carriers and perform radiative recombination to emit light, that is, increase the radiative recombination center, thereby improving the performance of the device. internal quantum efficiency, and ultimately improve the luminous efficiency of the device. The brightness and internal quantum efficiency of the LED obtained by adopting the manufacturing method of the LED epitaxial wafer provided by the invention are improved.

以上仅为本发明的优选实施例而已，并不用于限制本发明，对于本领域的技术人员来说，本发明可以有各种更改和变化。凡在本发明的精神和原则之内，所作的任何修改、等同替换、改进等，均应包含在本发明的保护范围之内。The above are only preferred embodiments of the present invention, and are not intended to limit the present invention. For those skilled in the art, the present invention may have various modifications and changes. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principles of the present invention shall be included within the protection scope of the present invention.

Claims (11)

Translated fromChinese

1.一种LED外延片，包括由衬底(10)表面向外依次设置的GaN层(20)、N型GaN层(30)、有源层(40)以及P型GaN层(50)，所述有源层(40)包括一组或多组量子阱层，其特征在于，各量子阱层由所述N型GaN层表面向外的方向上依次包括InGaN势阱层(41)、GaN势垒层(43)和MgN势垒层(45)。1. An LED epitaxial wafer, comprising a GaN layer (20), an N-type GaN layer (30), an active layer (40) and a P-type GaN layer (50) arranged outwards from the substrate (10) surface in sequence, The active layer (40) includes one or more sets of quantum well layers, characterized in that each quantum well layer includes an InGaN potential well layer (41), GaN A barrier layer (43) and a MgN barrier layer (45).2.根据权利要求1所述的外延片，其特征在于，在所述有源层(40)中包括10～13组所述量子阱层。2. The epitaxial wafer according to claim 1, characterized in that the active layer (40) includes 10-13 groups of quantum well layers.3.根据权利要求2所述的外延片，其特征在于，各组所述量子阱层中所述MgN势垒层(45)的厚度为0.3～1.0nm。3. The epitaxial wafer according to claim 2, characterized in that the thickness of the MgN barrier layer (45) in each group of quantum well layers is 0.3-1.0 nm.4.根据权利要求3所述的外延片，其特征在于，所述InGaN势阱层(41)的厚度为2.5～3.5nm，所述GaN势垒层(43)的厚度为10～13nm。4. The epitaxial wafer according to claim 3, characterized in that the thickness of the InGaN potential well layer (41) is 2.5-3.5 nm, and the thickness of the GaN barrier layer (43) is 10-13 nm.5.根据权利要求4所述的外延片，其特征在于，所述InGaN势阱层(41)中In的掺杂浓度为2E+20～5E+20atom/cm³。5 . The epitaxial wafer according to claim 4 , characterized in that, the doping concentration of In in the InGaN potential well layer ( 41 ) is 2E+20˜5E+20 atom/cm³ .6.一种LED外延片的制作方法，包括由衬底(10)表面向外依次形成GaN层(20)、N型GaN层(30)、有源层(40)以及P型GaN层(50)，所述形成有源层(40)的步骤包括：依次形成一组或多组量子阱层，其特征在于，形成各所述量子阱层的步骤包括：由所述N型GaN层(30)表面向外的方向，依次形成InGaN势阱层(41)、GaN势垒层(43)和MgN势垒层(45)。6. A method for manufacturing an LED epitaxial wafer, comprising sequentially forming a GaN layer (20), an N-type GaN layer (30), an active layer (40) and a P-type GaN layer (50) outward from the surface of a substrate (10) ), the step of forming an active layer (40) comprises: sequentially forming one or more groups of quantum well layers, wherein the step of forming each of the quantum well layers comprises: forming the N-type GaN layer (30 ) in the direction outward from the surface, sequentially forming an InGaN potential well layer (41), a GaN potential barrier layer (43) and a MgN potential barrier layer (45).7.根据权利要求6所述的制作方法，其特征在于，所述形成有源层(40)的步骤中依次形成10～13组量子阱层。7. The manufacturing method according to claim 6, characterized in that, in the step of forming the active layer (40), 10-13 groups of quantum well layers are sequentially formed.8.根据权利要求7所述的制作方法，其特征在于，形成所述MgN势垒层(45)的步骤包括：8. The manufacturing method according to claim 7, characterized in that, the step of forming the MgN barrier layer (45) comprises:采用与生长所述GaN势垒层(43)相同的温度和压力的氮气或混有少量氢气的氮气气氛下，通入镁源生长厚度为0.3～1.0nm的所述MgN势垒层(45)。growing the MgN barrier layer (45) with a thickness of 0.3-1.0 nm by injecting a magnesium source under nitrogen gas at the same temperature and pressure as that used for growing the GaN barrier layer (43) or a nitrogen gas atmosphere mixed with a small amount of hydrogen gas .9.根据权利要求8所述的制作方法，其特征在于，形成所述InGaN势阱层(41)和所述GaN势垒层(43)的步骤包括：9. The manufacturing method according to claim 8, characterized in that, the step of forming the InGaN potential well layer (41) and the GaN barrier layer (43) comprises:在温度为730～760℃，压力为150～300torr的氮气或混有少量氢气的氮气气氛下，通入镓源和铟源生长厚度为2.5～3.5nm，In的掺杂浓度为2E+20～5E+20atom/cm³的所述InGaN势阱层(41)；In the nitrogen atmosphere with a temperature of 730-760°C and a pressure of 150-300torr or a nitrogen gas mixed with a small amount of hydrogen, the gallium source and the indium source are introduced into the growth thickness of 2.5-3.5nm, and the doping concentration of In is 2E+20~ The InGaN potential well layer (41) of 5E+20atom/cm³ ;停止通入铟源，升温至840～890℃，保持压力不变，生长厚度为10～13nm的所述GaN势垒层(43)。Stop feeding the indium source, raise the temperature to 840-890° C., keep the pressure constant, and grow the GaN barrier layer (43) with a thickness of 10-13 nm.10.根据权利要求9所述的制作方法，其特征在于，10. The preparation method according to claim 9, characterized in that,在生长所述InGaN势阱层(41)的步骤中，以三乙基镓或三甲基镓作为镓源，三甲基铟作为铟源；In the step of growing the InGaN potential well layer (41), triethylgallium or trimethylgallium is used as the gallium source, and trimethylindium is used as the indium source;在生长所述GaN势垒层(43)的步骤中，以三乙基镓或三甲基镓作为镓源；In the step of growing the GaN barrier layer (43), triethylgallium or trimethylgallium is used as the gallium source;在生长所述MgN势垒层(45)的步骤中，以二茂镁作为镁源。In the step of growing the MgN barrier layer (45), magnesiumocene is used as a magnesium source.11.一种LED芯片，包括衬底、设置在所述衬底上的外延片，以及设置在所述外延片上的P电极和N电极，其特征在于，所述外延片为权利要求1至5中任一项所述的外延片。11. An LED chip, comprising a substrate, an epitaxial wafer disposed on said substrate, and a P electrode and an N electrode disposed on said epitaxial wafer, characterized in that said epitaxial wafer is one of claims 1 to 5 The epitaxial wafer described in any one.