High quality semiconductor epitaxial wafer and method of making the same

Abstract

The application discloses a high-quality semiconductor epitaxial wafer and a preparation method thereof. The preparation method comprises the following steps: providing a III group metal organic source mixed precursor containing uniformly dispersed nanomaterials, coating the III group metal organic source mixed precursor on a substrate to obtain a III group metal organic source mixed precursor coating layer, and then performing annealing recrystallization to obtain a stress release buffer layer; and then regrowing a semiconductor epitaxial structure to obtain the high-quality semiconductor epitaxial wafer. The application prepares a metal organic source coating layer on a substrate, and combines MOCVD reaction cavity annealing recrystallization, so that the nanomaterial dispersed metal organic source coating layer gradually forms two kinds of crystal nucleus distribution to provide nucleation centers, the stress of the epitaxial layer is gradually released, the lateral epitaxial growth is strengthened, the dislocation density extension of the epitaxial layer is inhibited, the defect density is reduced, the growth quality of a quantum well light-emitting layer is improved, the leakage performance and the light-emitting efficiency are improved, meanwhile, the light-emitting wavelength uniformity is improved, and the uniform performance requirement of the Micro-LED epitaxial wafer can be met.

Description

TECHNICAL FIELD

[0001] The present application relates to a high-quality semiconductor epitaxial wafer and a preparation method thereof, and belongs to the technical field of semiconductor material epitaxy. BACKGROUND

[0002] III-V compound semiconductor materials are widely used in optoelectronic devices, optoelectronic integration, ultra-high-speed microelectronic devices, and ultra-high-frequency microwave devices and circuits, and have broad prospects. Since III-nitride is generally grown heteroepitaxially on a heterogeneous substrate such as sapphire or SiC, the lattice constant and thermal mismatch between different materials will generate dislocations or defects, which will extend upward with the growth of the epitaxial layer. These dislocations act as non-radiative recombination centers when the device is working, affecting the device efficiency, and as leakage channels causing an increase in leakage current, which rapidly ages the device and affects the working efficiency and service life of the device, restricting its application in the field of semiconductor electronics. In addition, with the unprecedented development of Micro-LED display application fields, higher demands are placed on epitaxial uniformity. SUMMARY

[0003] The main purpose of the present application is to provide a high-quality semiconductor epitaxial wafer and a preparation method thereof based on the problem of epitaxial defects in the heteroepitaxy of semiconductor materials, in order to overcome the shortcomings of the prior art.

[0004] To achieve the above-mentioned purposes, the technical solutions adopted by the present application include:

[0005] The present application provides a preparation method of a high-quality semiconductor epitaxial wafer, which comprises:

[0006] Providing a III metal organic source mixed precursor containing uniformly dispersed nanomaterials;

[0007] Coating the III metal organic source mixed precursor on a substrate to obtain a III metal organic source mixed precursor coating layer, and then placing the substrate with the III metal organic source mixed precursor coating layer in a MOCVD reaction chamber, introducing a III metal organic source, and performing annealing recrystallization in a mixed atmosphere of a V element source and a reducing gas, thereby forming a uniformly distributed nanomaterial and a III-V compound nanogrowth structure to obtain a stress release buffer layer;

[0008] Growth of a semiconductor epitaxial structure on the stress release buffer layer to obtain a high-quality semiconductor epitaxial wafer.

[0009] In some embodiments, the nanomaterials include any one or a combination of zero-dimensional nanomaterials, one-dimensional nanomaterials, two-dimensional nanomaterials, and three-dimensional nanomaterials.

[0010] In some embodiments, the group III element contained in the group III metal organic source includes any one or a combination of two or more of indium, gallium, and aluminum.

[0011] Further, the group V element contained in the group V element source includes any one or a combination of two or more of nitrogen, phosphorus, and arsenic.

[0012] Further, the preparation method further includes: sequentially growing, on the stress release buffer layer, an unintentionally doped nitride layer, an n-type nitride layer, a light emitting layer, an electron blocking layer, and a p-type nitride layer to obtain a high-quality semiconductor epitaxial wafer.

[0013] The embodiment of the present application also provides a high-quality semiconductor epitaxial wafer prepared by the aforementioned method, including a substrate, and a stress release buffer layer and a semiconductor epitaxial structure sequentially formed on the substrate; wherein the stress release buffer layer is formed by annealing and recrystallization of a group III metal organic source mixed precursor coating layer coated on the surface of the substrate.

[0014] Further, the high-quality semiconductor epitaxial wafer includes a substrate and, sequentially, a stress release buffer layer, an unintentionally doped nitride layer, an n-type nitride layer, a light emitting layer, an electron blocking layer, and a p-type nitride layer.

[0015] Compared with the prior art, the present application has remarkable advantages and beneficial effects, which are embodied in the following aspects:

[0016] The present application provides a spin-coated epitaxial wafer with uniformly dispersed nanomaterials and a preparation method, a group III metal organic source mixed precursor coating layer is prepared on a substrate by a spin coating method, the thickness is precisely controllable and the process is stable, and meanwhile, in combination with the annealing and recrystallization process of the MOCVD reaction chamber, the nanomaterial-dispersed group III metal organic source coating layer gradually forms two kinds of crystal nucleus distribution to provide nucleation centers, the stress of the epitaxial layer is gradually released, the lateral epitaxial growth is strengthened, the dislocation density extension of the epitaxial layer is inhibited, the defect density is reduced, the growth quality of the quantum well light emitting layer is improved, the leakage performance and the light emitting efficiency are improved, meanwhile, the low stress quantum well light emitting layer improves the uniformity of the light emitting wavelength, and can meet the uniform performance requirements of Micro-LED epitaxial.

[0017] Other features and advantages of the present application will be set forth in the following description, and in part will become apparent from the description, or can be learned by practice of the present application according to the working examples. The objects and other advantages of the present application will be realized and achieved by means of the structures particularly pointed out in the written description and claims, and the accompanying drawings. BRIEF DESCRIPTION OF DRAWINGS

[0018] In order to more clearly illustrate the technical solutions in the embodiments of the present application or the prior art, the following will briefly introduce the drawings needed to be used in the embodiments or prior art description. Obviously, the drawings in the following description only represent some embodiments of the present application, and for those skilled in the art, other drawings can be obtained without creative effort based on these drawings.

[0019] Figure 1 is a preparation flowchart of a high-quality light emitting diode epitaxial structure in a typical embodiment of the present application.

[0020] Figure 2 is a schematic diagram of a layered structure of a high-quality light emitting diode epitaxial structure in a typical embodiment of the present application.

[0021] Legend: 1-substrate, 2-stress release buffer layer, 3-non-intentionally doped nitride layer, 4-n-type nitride layer, 5-light emitting layer, 51-InGaN quantum well layer, 52-GaN quantum barrier layer, 6-electron blocking layer, 7-p-type nitride layer. DETAILED DESCRIPTION

[0022] The technical solutions in the embodiments of the present application will be described clearly and completely below with reference to the drawings in the embodiments of the present application. Obviously, the described embodiments only represent some of the embodiments of the present application, rather than all the embodiments. The components of the embodiments of the present application described and shown in the drawings herein can be arranged and designed in various different configurations. Therefore, the following detailed description of the embodiments of the present application provided in the drawings is not intended to limit the scope of the claimed present application, but only represents selected embodiments of the present application. Based on the embodiments of the present application, those skilled in the art should understand that the technical solutions of the embodiments can still be modified, or some technical features can be replaced by equivalent features; and these modifications or replacements do not make the corresponding technical solutions deviate from the spirit and scope of the technical solutions of the embodiments of the present application, and all other embodiments obtained without creative effort are within the scope of the present application.

[0023] It should be noted that similar reference numerals and letters represent similar items in the following drawings, and therefore, once an item is defined in one drawing, it does not need to be further defined and explained in subsequent drawings. Meanwhile, in the description of the present application, orientation terms and order terms, etc. are only used for distinguishing description, and cannot be understood as indicating or implying relative importance.

[0024] The technical solutions, implementation process and principles, etc. will be further explained as follows.

[0025] One aspect of the embodiments of the present application provides a high-quality semiconductor epitaxial wafer, comprising a substrate, a stress release buffer layer and a semiconductor epitaxial structure formed on the substrate in sequence; wherein the stress release buffer layer is formed by annealing and recrystallization of a III-group metal organic source mixed precursor coating layer coated on the surface of the substrate.

[0026] Further, the thickness of the metal organic source coating layer is 20-2000 nm.

[0027] Further, the nanomaterials include, but are not limited to, any one or combination of zero-dimensional nanomaterials, one-dimensional nanomaterials, two-dimensional nanomaterials and three-dimensional nanomaterials.

[0028] Another aspect of the embodiments of the present application provides a method for preparing a high-quality semiconductor epitaxial wafer, comprising:

[0029] providing a III-group metal organic source mixed precursor containing uniformly dispersed nanomaterials;

[0030] coating the III-group metal organic source mixed precursor on a substrate to obtain a III-group metal organic source mixed precursor coating layer, and then placing the substrate with the III-group metal organic source mixed precursor coating layer in a MOCVD reaction chamber, introducing a III-group metal organic source, and performing annealing and recrystallization in a mixed atmosphere of a V-group element source and a reducing gas, so as to form uniformly distributed nanomaterials and III-V compound nanogrowth structures, thereby obtaining a stress release buffer layer;

[0031] growing a semiconductor epitaxial structure on the stress release buffer layer to obtain a high-quality semiconductor epitaxial wafer.

[0032] In some embodiments, the nanomaterials include, but are not limited to, any one or combination of zero-dimensional nanomaterials, one-dimensional nanomaterials, two-dimensional nanomaterials and three-dimensional nanomaterials.

[0033] Further, the mass ratio of the nanomaterials to the III-group metal organic source in the mixed precursor is less than 1:1.

[0034] In some embodiments, the nanomaterials can be nanoparticles, preferably any one or combination of metal nanomaterials, non-metal inorganic nanomaterials, organic compound nanomaterials and the like, and a plurality of nanoparticles coexist in the dispersion liquid without reaction with each other, and still exist as individual nanoparticles in the dispersion liquid.

[0035] Further, the morphology of the nanomaterials can be any one or combination of nanoparticles, nanowires, nanofilms, nanoblocks and the like, but is not limited thereto.

[0036] In some embodiments, the nanomaterial (i.e., nanoparticle) can be any one or a combination of two or more of Si3N4, SiO2, GaN, AlN, InN, SiC, ScAlN, Al2O3, Si, C, TiC, TiN, WC, WC-CO, B4C, BN, TiB2, LaF3, MoS2, ZrB2, ZnS, ZnSe, ZnO, Fe3O4, Ta2O5, SnO2, TiO2, ZrO2, Ni, Au, Ag, Fe, Co, Mn, Ti, Mg, Al, Ga, In, polystyrene, perovskite, graphene, etc., but not limited thereto, and can be any other possible nanoparticle.

[0037] Further, the nanomaterial can preferably include any one or a combination of two or more of SiN, SiO2, GaN, AlN, InN, SiC, ScAlN, Al2O3, Si, C, TiC, TiN, BN, ZnS, ZnSe, ZnO, TiO2, Ni, Au, Ag, Fe, Co, Mn, Ti, Mg, Al, graphene, etc.

[0038] Still further, the nanomaterial can preferably include any one or a combination of two or more of SiN, GaN, AlN, SiC, ScAlN, Al2O3, TiO2, Ni, Al, Ga, graphene, etc.

[0039] Further, the nanomaterial can have a diameter of 5 to 500 nm.

[0040] In some embodiments, the group III metal organic source can include a group III element including any one or a combination of two or more of indium (In), gallium (Ga), and aluminum (Al).

[0041] Further, the group III metal organic source can include a group III organic compound source including any one or a combination of two or more of an indium source, a gallium source, and an aluminum source.

[0042] The indium (In) source can include one or a combination of two or more of trimethyl indium, triethyl indium, and dimethyl ethyl indium, the gallium (Ga) source can include one or a combination of two or more of trimethyl gallium (TMG), triethyl gallium, and triisopropyl gallium, and the aluminum source can include any one or a combination of two or more of trimethyl aluminum, triethyl aluminum, dimethyl aluminum hydride, dimethyl aluminum, and an aluminum alkane complex, but not limited thereto.

[0043] In some embodiments, the group V element source can include a group V element including any one or a combination of two or more of nitrogen (N), phosphorus (P), and arsenic (As).

[0044] Further, the Group V element source includes any one of a nitrogen source, a phosphorus source, an arsenic source, or a combination of two or more thereof.

[0045] The nitrogen source includes NH3, an organic amine compound, a trap compound, or a combination of two or more thereof, but is not limited thereto. The organic amine compound can be an alkyl amine such as t-butyl amine, n-propyl amine, or the like, and the trap compound can be dimethyl trap, but is not limited thereto.

[0046] The phosphorus source includes PH3 and / or an organic phosphorus source, and the organic phosphorus source includes t-butyl phosphine, but is not limited thereto.

[0047] The arsenic source includes AsH3 and / or an organic arsenic source, and the organic arsenic source includes t-butyl arsenic, but is not limited thereto.

[0048] Further, the reducing gas preferably includes H2, but is not limited thereto.

[0049] Further, the flow ratio of the Group V element source to the reducing gas in the mixed atmosphere is 10:1 to 100:1.

[0050] Further, the III metal organic source mixed precursor coating layer has a thickness of 20 to 2000 nm.

[0051] In some embodiments, the preparation method further includes sequentially growing an unintentionally doped nitride layer, an n-type nitride layer, a light emitting layer, an electron blocking layer, and a p-type nitride layer on the stress release buffer layer to obtain a high-quality semiconductor epitaxial wafer.

[0052] Further, the substrate can be sapphire, silicon carbide, silicon, zinc oxide, gallium nitride, or gallium arsenide, but is not limited thereto.

[0053] In some specific embodiments, the preparation method of the III metal organic source mixed precursor with uniformly dispersed nanomaterials on the substrate by spin coating includes the following steps:

[0054] 1) Preparation of nanomaterial dispersion

[0055] The nanomaterial is added to the dispersion solvent and mixed, a dispersant is added to prevent spontaneous agglomeration of the nanoparticles due to high surface energy, and the nanoparticles are uniformly dispersed in the solvent under ultrasonic conditions at a certain temperature to form a nanomaterial dispersion;

[0056] 2) Preparation of III metal organic source mixed precursor containing uniformly dispersed nanomaterials

[0057] separating the nanomaterial from the solvent, rapidly drying the nanomaterial, mixing the nanomaterial with a proper amount of the Group III metal organic source, and obtaining the Group III metal organic source mixed precursor containing uniformly dispersed nanomaterial under ultrasonic condition at a certain temperature;

[0058] 3) spin-coating the Group III metal organic source mixed precursor containing uniformly dispersed nanomaterial

[0059] 3) spin-coating the Group III metal organic source mixed precursor containing uniformly dispersed nanomaterial

[0060] Specifically, the step 2) specifically comprises: uniformly mixing the nanomaterial with the Group III metal organic source, and ultrasonically treating the mixture at 5-40℃ for 10-60 min to obtain the Group III metal organic source mixed precursor containing uniformly dispersed nanomaterial.

[0061] Specifically, before the step 1), the nanomaterial is uniformly dispersed in a dispersion solvent and ultrasonically treated to form a nanomaterial dispersion liquid, and then the nanomaterial is separated from the dispersion solvent and dried, wherein the dispersion solvent comprises ethanol, the ultrasonic treatment time is 0.5-2 h, and the nanomaterial dispersion liquid further comprises a dispersant.

[0062] Further, the high-quality semiconductor epitaxial wafer is a light emitting diode (LED) epitaxial wafer.

[0063] In some more specific embodiments, please refer to Figure 1 As shown in the figure, the preparation method of the high-quality light emitting diode epitaxial wafer specifically comprises the following steps:

[0064] 1) providing a substrate, which can be sapphire, silicon carbide, silicon, zinc oxide or gallium nitride;

[0065] 2) in a glove box under N2 atmosphere, spin-coating the Group III metal organic source mixed precursor containing uniformly dispersed nanomaterial on the substrate by using a spin-coating method to form a Group III metal organic source mixed precursor coating layer with a thickness of 20 nm-2000 nm on the substrate;

[0066] 3) placing the substrate with the Group III metal organic source mixed precursor coating layer into a reaction chamber of a MOCVD growth device, and growing an epitaxial layer by using an epitaxial growth process as follows:

[0067] The substrate with the mixed precursor coating layer of the III metal organic source is placed in the reaction chamber of the MOCVD growth equipment, the pressure in the reaction chamber is 100-600 torr, the III metal organic source, which is the III organic compound source, is introduced, the reaction chamber is heated to 500-1200℃, and the V element source and the reducing gas are introduced for annealing recrystallization for 10-100 s, and then the stress release buffer layer with a thickness of 10-100 nm is grown;

[0068] 4) A non-intentionally doped nitride layer with a thickness of 1-4 μm is grown on the stress release buffer layer, the non-intentionally doped nitride layer is a non-intentionally doped GaN layer, the Ga source required for growth is a TMG source, the growth atmosphere is an H2 atmosphere, the growth temperature is 1000-1200℃, and the growth pressure is 100-600 torr;

[0069] 5) An n-type nitride layer with a thickness of 1-4 μm is grown on the non-intentionally doped nitride layer, the n-type nitride layer is an n-type GaN layer, the Si doping concentration is 2×10 18 cm -3 -5×10 19 cm -3 ; the Ga source required for growth is a TMG source, the growth atmosphere is an H2 atmosphere, the growth temperature is 1000-1200℃, and the growth pressure is 100-600 torr;

[0070] 6) A light-emitting layer is grown on the n-type nitride layer, 1-20 pairs of InGaN / GaN multi-quantum well light-emitting layers are co-grown, the InGaN / GaN multi-quantum well light-emitting layer comprises periodically and alternately grown InGaN quantum well layers and GaN quantum barrier layers, the repeating period is 1-20, the thickness of the InGaN quantum well layer is 2-6 nm, the Ga source required for growth is a TEG source, the In source is a TMIn source, the growth atmosphere is an N2 atmosphere, the growth temperature is 700-900℃, and the growth pressure is 200-500 torr; the thickness of the GaN quantum barrier layer is 6-20 nm, the Ga source required for growth is a TEG source, the growth atmosphere is an H2 atmosphere, the growth temperature is 750-950℃, and the growth pressure is 200-500 torr;

[0071] 7) An electron blocking layer with a thickness of 15-150 nm is grown on the light-emitting layer, the electron blocking layer is a p-type AlGaN electron blocking layer, the Ga source required for growth is a TMG source, the Al source is a TMAl source, the growth atmosphere is an N2 atmosphere, the growth temperature is 950-1050℃, and the growth pressure is 100-200 torr;

[0072] 8) growing a p-type nitride layer with a thickness of 20-200 nm on the electron barrier layer, the p-type nitride layer being a p-type GaN layer, the doping concentration of Mg being 1×10 18 em -3 ~5×10 20 cm -3 ; the Ga source required for growth is a TMG source, the growth atmosphere is an H2 atmosphere, the growth temperature is 950-1050℃, and the growth pressure is 200-600 torr.

[0073] Another aspect of the embodiment of the present application also provides a high-quality semiconductor epitaxial wafer prepared by the aforementioned method.

[0074] Specifically, the high-quality semiconductor epitaxial wafer comprises a substrate, and a stress release buffer layer and a semiconductor epitaxial structure are sequentially formed on the substrate; wherein the stress release buffer layer is formed by annealing and recrystallization of a III-metal organic source mixed precursor coating layer coated on the surface of the substrate.

[0075] Further, the high-quality semiconductor epitaxial wafer is a light emitting diode (LED) epitaxial wafer.

[0076] Further, the thickness of the III-metal organic source mixed precursor coating layer is 20-2000 nm.

[0077] Further, the high-quality semiconductor epitaxial wafer comprises a substrate and a stress release buffer layer, an unintentionally doped nitride layer, an n-type nitride layer, a light emitting layer, an electron barrier layer, and a p-type nitride layer sequentially located on the substrate.

[0078] Further, the substrate can be sapphire, silicon carbide, silicon, zinc oxide, gallium nitride, gallium arsenide, etc., but is not limited thereto.

[0079] Further, the unintentionally doped nitride layer is an unintentionally doped GaN layer with a thickness of 1-4 μm.

[0080] Further, the n-type nitride layer is an n-type GaN layer with a thickness of 1-4 μm, and the doping concentration of Si is 2×10 18 em -3 ~5×10 19 cm -3 .

[0081] Further, the light emitting layer is an InGaN / GaN multi-quantum well light emitting layer, which comprises periodically and alternately grown InGaN quantum well layers and GaN quantum barrier layers, the repeating period being 1-20, the thickness of the InGaN quantum well layer being 2-6 nm, and the thickness of the GaN quantum barrier layer being 6-20 nm.

[0082] Further, the electron blocking layer is a p-type AlGaN electron blocking layer with a thickness of 15-150 nm.

[0083] Further, the p-type nitride layer is a p-type GaN layer with a thickness of 20-200 nm and a Mg doping concentration of 1 x 1018-5 x 1019 cm-3. 18 cm -3 ~5 x 10 20 cm -3

[0084] Specifically, as shown in the drawing, the high-quality semiconductor epitaxial wafer of the present application comprises a substrate 1 and, in sequence, a stress release buffer layer 2, an unintentionally doped nitride layer 3, an n-type nitride layer 4, a light emitting layer 5, an electron blocking layer 6, and a p-type nitride layer 7. Figure 2

[0085] The substrate 1 is a sapphire, silicon carbide, silicon, zinc oxide, gallium nitride, gallium arsenide, or other material substrate.

[0086] Further, the stress release buffer layer 2 is formed by annealing and recrystallizing a III-group metal organic source mixed precursor coating layer obtained by spin coating a III-group metal organic source mixed precursor containing uniformly dispersed nanometer materials, and the thickness of the III-group metal organic source mixed precursor coating layer is 20-2000 nm.

[0087] Further, the unintentionally doped nitride layer 3 is an unintentionally doped GaN layer with a thickness of 1-4 μm.

[0088] Further, the n-type nitride layer 4 is an n-type GaN layer with a thickness of 1-4 μm and a Si doping concentration of 2 x 1018-5 x 1019 cm-3. 18 cm -3 ~5 x 10 19 cm -3

[0089] Further, the light emitting layer 5 is a cyclically grown 1-20 pairs of InGaN / GaN multi-quantum well light emitting layer, the thickness of the InGaN quantum well layer 51 is 2-6 nm, and the thickness of the GaN quantum barrier layer 52 is 6-20 nm.

[0090] Further, the electron blocking layer 6 is a p-type AlGaN electron blocking layer with a thickness of 15-150 nm.

[0091] Further, the p-type nitride layer 7 is a p-type GaN layer with a thickness of 20-200 nm and a Mg doping concentration of 1 x 1018-5 x 1019 cm-3. 18 cm -3 ~5 x 10 20 cm -3 ​​​.

[0092] The technical solutions, implementation process and principles of the embodiments of the present application will be further explained in combination with the embodiments and drawings.

[0093] Embodiment 1

[0094] 1) Preparation of Ni nanoparticle dispersion

[0095] Anhydrous ethanol was used, 30% by mass of Ni powder with a diameter of 30-80 nm was added, and 0.15% by mass of citric acid dispersant was added, and ultrasonic treatment was performed at room temperature for 2 hours;

[0096] 2) Preparation of TMG source of Ni nanoparticles

[0097] The Ni nanoparticles were separated from the solvent, and immediately mixed with a high-purity TMG source, with a mass fraction of 40% of the Ni nanoparticles, and ultrasonic treatment was performed at 40°C for 60 minutes, to obtain a TMG source mixed precursor of uniformly dispersed Ni nanoparticles;

[0098] 3) Spin coating of TMG source mixed precursor of Ni nanoparticles

[0099] In a glove box under N2 atmosphere, the TMG source mixed precursor of Ni nanoparticles was spin coated on a sapphire substrate by a spin coater at a rotation speed of 4000 rpm, to form a TMG source mixed precursor coating layer of uniformly dispersed Ni nanoparticles on the substrate, with a thickness of 30 nm;

[0100] 4) Growth of LED epitaxial wafer on TMG source mixed precursor coating layer

[0101] ①The substrate 1 with the TMG source mixed precursor coating layer of dispersed Ni nanoparticles was placed in a MOCVD reaction chamber, the pressure was set to 500 torr, the TMG source was introduced, the temperature was set to 1060°C, NH3 and H2 were introduced for annealing recrystallization for 10 seconds, the flow ratio of NH3 and H2 was 10:1, and a GaN stress release buffer layer 2 was grown;

[0102] ②On the GaN stress release buffer layer 2, a non-intentionally doped nitride layer 3 with a thickness of 4 μm was grown under the conditions of a temperature of 1080°C and a growth pressure of 200 torr, which was a non-intentionally doped GaN layer, the required Ga source was a TMG source, and the growth atmosphere was an H2 atmosphere;

[0103] ③On the non-intentionally doped nitride layer 3, an n-type nitride layer 4 with a thickness of 1 μm was grown under the conditions of a temperature of 1060°C and a growth pressure of 200 torr, which was an n-type GaN layer, the doping concentration of Si was 8×10 18 cm -3The Ga source required for growth is a TMG source, and the growth atmosphere is an H2 atmosphere;

[0104] (4) On the n-type nitride layer 4, a light-emitting layer 5 is grown, which is a pair of InGaN / GaN multiple quantum well light-emitting layers 6 repeatedly grown. The thickness of the InGaN quantum well layer 51 is 3 nm, the growth temperature is 750°C, the growth pressure is 200 torr, the growth atmosphere is switched to an N2 atmosphere, the thickness of the GaN quantum barrier layer 52 is 11 nm, the growth temperature is 810°C, the growth atmosphere is switched to an H2 atmosphere, the growth pressure is 200 torr, the Ga source required for growth is a TEGa source, and the In source is a TMIn source;

[0105] (5) On the InGaN / GaN multiple quantum well light-emitting layer 5, an electron blocking layer 6 is grown, which is a p-type AlGaN electron blocking layer with a thickness of 25 nm, at a temperature of 950°C and a growth pressure of 200 torr. The Ga source required for growth is a TMG source, the Al source is a TMAl source, and the growth atmosphere is an N2 atmosphere;

[0106] (6) On the electron blocking layer 6, a p-type nitride layer 7 is grown, which is a p-type GaN layer with a thickness of 50 nm, a Mg doping concentration of 5x1019cm-3, and a growth temperature of 950°C. The Ga source required for growth is a TMG source, and the growth atmosphere is switched to an H2 atmosphere. 19 cm -3 The Ga source required for growth is a TMG source, and the growth atmosphere is switched to an H2 atmosphere.

[0107] Example 2

[0108] 1) Preparation of a Ni nanoparticle dispersion

[0109] Anhydrous ethanol is used, 30% by mass of Ni nanopowder with a diameter of 30-80 nm is added, and 0.15% by mass of citric acid dispersant is added. The mixture is ultrasonically treated at room temperature for 2 hours.

[0110] 2) Preparation of a TMG source of Ni nanoparticles

[0111] The Ni nanoparticles are separated from the solvent, and immediately mixed with a high-purity TMG source. The mass fraction of the Ni nanoparticles is 40%, and the mixture is ultrasonically treated at 40°C for 60 minutes to obtain a TMG source mixed precursor of uniformly dispersed Ni nanoparticles.

[0112] 3) Spin coating of a TMG source mixed precursor of Ni nanoparticles

[0113] In a glove box under an N2 atmosphere, the TMG source mixed precursor of uniformly dispersed Ni nanoparticles is spin coated on a sapphire substrate at a rotation speed of 4000 rpm by means of a spin coater. A TMG source mixed precursor coating layer of uniformly dispersed Ni nanoparticles with a thickness of 800 nm is formed on the substrate.

[0114] 4) TMG source mixed precursor coated layer on LED epitaxial wafer growth

[0115] ① Put the substrate 1 with TMG source mixed precursor coated layer with dispersed Ni nanoparticles into the MOCVD reaction chamber, set the pressure to 300 torr, input TMG source, set the temperature to 1200℃, input NH3 and H2 to anneal and recrystallize for 40s, the flow ratio of NH3 and H2 is 20:1, and grow GaN stress release buffer layer 2;

[0116] ② On the GaN stress release buffer layer 2, grow a non-intentionally doped nitride layer 3 with a thickness of 2.5μm under the conditions of a temperature of 1080℃ and a growth pressure of 200 torr, which is a non-intentionally doped GaN layer, the required Ga source is TMG source, and the growth atmosphere is H2 atmosphere;

[0117] ③ On the non-intentionally doped nitride layer 3, grow an n-type nitride layer 4 with a thickness of 2.5μm under the conditions of a temperature of 1060℃ and a growth pressure of 200 torr, which is an n-type GaN layer, the Si doping concentration is 8×10 18 cm -3 , the required Ga source for growth is TMG source, and the growth atmosphere is H2 atmosphere;

[0118] ④ On the n-type nitride layer 4, grow a light-emitting layer 5, which is a repeated growth of 6 pairs of InGaN / GaN multi-quantum well light-emitting layers, the thickness of the InGaN quantum well layer 51 is 3nm, the growth temperature is 750℃, the growth atmosphere is switched to N2 atmosphere, the growth pressure is 200 torr, the thickness of the GaN quantum barrier layer 52 is 11nm, the growth temperature is 810℃, the growth atmosphere is switched to H2 atmosphere, the growth pressure is 200 torr, the required Ga source for growth is TEGa, and the In source is TMIn;

[0119] ⑤ On the InGaN / GaN multi-quantum well light-emitting layer 5, grow an electron blocking layer 6 with a thickness of 25nm under the conditions of a temperature of 950℃ and a growth pressure of 200 torr, which is a p-type AlGaN electron blocking layer, the required Ga source for growth is TMG source, the Al source is TMAl, and the growth atmosphere is N2 atmosphere;

[0120] ⑥ On the electron blocking layer 6, grow a p-type nitride layer 7 with a thickness of 50nm under the conditions of a temperature of 950℃ and a growth pressure of 200 torr, which is a p-type GaN layer, the Mg doping concentration is 5×10 19 cm -3 , the required Ga source for growth is TMG source, and the growth atmosphere is switched to H2 atmosphere.

[0121] Example 3

[0122] 1) Preparation of Ni nanoparticle dispersion liquid

[0123] Anhydrous ethanol was used, 30% by mass of Ni nanopowder with a diameter of 30-80 nm was added, 0.15% by mass of citric acid dispersant was added, and ultrasonic treatment was performed at room temperature for 2 hours;

[0124] 2) Preparation of Ni nanoparticle TMG source

[0125] The Ni nanoparticles were separated from the solvent, and immediately mixed with a high-purity TMG source, with a Ni nanoparticle mass fraction of 40%, and ultrasonic treatment was performed at 25°C for 30 minutes to obtain a uniformly dispersed Ni nanoparticle TMG source mixed precursor;

[0126] 3) Spin coating of Ni nanoparticle TMG source mixed precursor

[0127] In a glove box under N2 atmosphere, the Ni nanoparticle TMG source mixed precursor was spin coated on a sapphire substrate at a speed of 4000 rpm by using a spin coater, and a TMG source mixed precursor coating layer with a thickness of 1800 nm of uniformly dispersed Ni nanoparticles was formed on the substrate;

[0128] 4) Growth of LED epitaxial wafer on TMG source mixed precursor coating layer

[0129] ①The substrate 1 with the TMG source mixed precursor coating layer of dispersed Ni nanoparticles was placed in the MOCVD reaction chamber, the pressure was set to 200 torr, the TMG source was introduced, the temperature was set to 1200°C, NH3 and H2 were introduced for annealing and recrystallization for 100 seconds, the flow ratio of NH3 and H2 was 50:1, and a GaN stress release buffer layer 2 was grown;

[0130] ②On the GaN stress release buffer layer 2, a 1 μm thick unintentionally doped nitride layer 3 was grown under the conditions of a temperature of 1080°C and a growth pressure of 200 torr, which was an unintentionally doped GaN layer, the required Ga source was a TMG source, and the growth atmosphere was an H2 atmosphere;

[0131] ③On the unintentionally doped nitride layer 3, a 4 μm thick n-type nitride layer 4 was grown under the conditions of a temperature of 1060°C and a growth pressure of 200 torr, which was an n-type GaN layer, the Si doping concentration was 8×10 18 cm -3 , the required Ga source was a TMG source, and the growth atmosphere was an H2 atmosphere;

[0132] (4) On the n-type nitride layer 4, a light emitting layer 5 is grown, which is 8 pairs of InGaN / GaN multiple quantum well light emitting layers repeatedly grown, the thickness of the InGaN quantum well layer 51 is 3 nm, the growth temperature is 750°C, the growth atmosphere is switched to N2 atmosphere, the growth pressure is 300 torr, the thickness of the GaN quantum barrier layer 52 is 11 nm, the growth temperature is 810°C, the growth atmosphere is switched to H2 atmosphere, the growth pressure is 300 torr, and the Ga source required for growth is TEGa, and the In source is TMIn;

[0133] (5) On the InGaN / GaN multiple quantum well light emitting layer 5, an electron blocking layer 6 with a thickness of 25 nm is grown at a temperature of 950°C and a growth pressure of 200 torr, which is a p-type AlGaN electron blocking layer, and the Ga source required for growth is a TMG source, the Al source is TMAl, and the growth atmosphere is N2 atmosphere;

[0134] (6) On the electron blocking layer 6, a p-type nitride layer 7 with a thickness of 50 nm is grown at a temperature of 950°C and a growth pressure of 200 torr, which is a p-type GaN layer, the Mg doping concentration is 5×10 19 cm -3 , the Ga source required for growth is a TMG source, and the growth atmosphere is switched to H2 atmosphere.

[0135] The surface roughness Ra of the LED epitaxial wafer obtained in Example 1, Example 2 and Example 3 is less than 0.7, the uniformity of the thickness of the epitaxial layer is less than 2%, the photoluminescence PL test 470 nm blue light wave half-width is less than 18 nm, and the wavelength uniformity std is less than 1.0 nm, which can meet the requirements of miro-LED on wavelength uniformity.

[0136] It is found that as the thickness of the unintentionally doped nitride layer increases from Example 1 to Example 3, the surface defects of the epitaxial wafer decrease from 5×10 8 cm -2 to 1×10 8 cm -2 It is found that as the thickness of the n-type nitride layer increases from Example 1 to Example 3, the point measurement brightness of the electroluminescence of the epitaxial wafer increases from 132 in Example 1 to 256, and the point measurement voltage decreases from 4.5V to 3.2V, so the thickness of the unintentionally doped nitride layer and the n-type nitride layer can be matched by controlling the TMG source mixed precursor coating layer annealing and recrystallization in combination with actual application, to meet different requirements of the surface defects and photoelectric performance of the epitaxial wafer.

[0137] The inventors of the present application also spin-coat a TMG source precursor layer of different uniformly dispersed metal nanoparticles (such as Au, Ag, Fe, Co, Mn, Ti, Mg, Al, Ga, In, etc.) as a stress release buffer layer, which, through testing, can reduce dislocation density and residual stress, improve quantum well light-emitting layer growth quality, improve leakage performance and light-emitting efficiency, and improve light-emitting wavelength uniformity, and can meet the requirements for Micro-LED epitaxial uniformity.

[0138] Example 4

[0139] 1) Preparation of Si3N4 nanoparticle dispersion

[0140] Anhydrous ethanol is used, 10% by mass of Si3N4 nanopowder with a diameter of 30-80 nm is added, and 0.15% by mass of citric acid dispersant is added, and ultrasonic treatment is performed at room temperature for 30 min;

[0141] 2) Preparation of Si3N4 nanoparticle TMG source

[0142] The Si3N4 nanoparticles are separated from the solvent, and immediately mixed with high-purity TMG source after rapid drying, the mass fraction of Si3N4 nanoparticles is 10%, and ultrasonic treatment is performed at 25°C for 30 min to obtain a TMG source mixed precursor of uniformly dispersed Si3N4 nanoparticles;

[0143] 3) Spin-coating of Si3N4 nanoparticle TMG source mixed precursor

[0144] In a glove box under N2 atmosphere, the Si3N4 nanoparticle TMG source mixed precursor is spin-coated on a sapphire substrate at a speed of 4000 rpm by using a spin coater, and a TMG source mixed precursor coating layer of uniformly dispersed Si3N4 nanoparticles with a thickness of 80 nm is formed on the substrate;

[0145] 4) Growth of LED epitaxial wafer on MO source coating layer

[0146] ①The sapphire substrate with the TMG source mixed precursor coating layer of uniformly dispersed Si3N4 nanoparticles is placed in a MOCVD reaction chamber, the pressure is set to 300 torr, the TMG source is introduced, the temperature is set to 1200°C, and NH3 and H2 are introduced for annealing and recrystallization for 15 s, the flow ratio of NH3 and H2 is 80:1, and a GaN stress release buffer layer 2 is prepared;

[0147] ②On the GaN stress release buffer layer 2, a non-intentionally doped nitride layer 3 with a thickness of 3 μm is grown at a temperature of 1080°C and a growth pressure of 200 torr, which is a non-intentionally doped GaN layer, the required Ga source is a TMG source, and the growth atmosphere is H2 atmosphere;

[0148] III. Growth of the n-type nitride layer 4 on the unintentionally doped nitride layer 3 at a temperature of 1060 °C and a growth pressure of 200 torr, with a thickness of 3 μm, as an n-type GaN layer, with a Si doping concentration of 8 x 1018cm-3, using a TMG source as the Ga source, and in a H2 atmosphere; 18 cm -3

[0149] IV. Growth of the light emitting layer 5 on the n-type nitride layer 4 as a 6-pair InGaN / GaN multiple quantum well light emitting layer, with a thickness of 3 nm for the InGaN quantum well layer 51, at a growth temperature of 770 °C, with a growth atmosphere switched to a N2 atmosphere, and a growth pressure of 300 torr, and a thickness of 11 nm for the GaN quantum barrier layer 52, at a growth temperature of 825 °C, with a growth atmosphere switched to a H2 atmosphere, and a growth pressure of 300 torr, using a TEGa source as the Ga source, and a TMIn source as the In source;

[0150] V. Growth of an electron blocking layer 6 on the InGaN / GaN multiple quantum well light emitting layer 5, with a thickness of 15 nm, as a p-type AlGaN electron blocking layer, at a temperature of 1000 °C and a growth pressure of 200 torr, using a TMG source as the Ga source, a TMAl source as the Al source, and in a N2 atmosphere;

[0151] VI. Growth of a p-type nitride layer 7 on the electron blocking layer 6, with a thickness of 20 nm, as a p-type GaN layer, with a Mg doping concentration of 5 x 1018cm-3, at a temperature of 950 °C and a growth pressure of 300 torr, using a TMG source as the Ga source, and in a H2 atmosphere. 19 cm -3

[0152] The LED epitaxial wafer obtained in this example has an epitaxial layer thickness uniformity of less than 2%, a photoluminescence (PL) test 470 nm blue light wave half-width of 18.7 nm, a wavelength uniformity std of 0.85 nm, and a 0405 chip size test leakage IR yield of 98.5%.

[0153] Example 5

[0154] 1) Preparation of an Al2O3 nanoparticle dispersion

[0155] Anhydrous ethanol is used, with the addition of 15% by mass of Al2O3 nanopowder with a diameter of 50-200 nm, and 0.15% by mass of a citric acid dispersant, and ultrasonic treatment is performed at room temperature for 30 min;

[0156] 2) Preparation of an Al2O3 nanoparticle TMG source

[0157] ​​The Al2O3 nanoparticles are separated from the solvent, quickly dried and immediately mixed with the high-purity TMG source, the mass fraction of the Al2O3 nanoparticles is 15%, and the TMG source mixed precursor of the uniformly dispersed Al2O3 nanoparticles is obtained by ultrasonic treatment for 60 min at 15°C;

[0158] 3) Spin-coating the TMG source mixed precursor of the Al2O3 nanoparticles

[0159] In the glove box under N2 atmosphere, the Al2O3 nanoparticle TMG source mixed precursor is spin-coated on the sapphire substrate 1 at a rotation speed of 2000 rpm by using the spin coater, and a TMG source mixed precursor coating layer of the uniformly dispersed Al2O3 nanoparticles with a thickness of 80 nm is formed on the substrate;

[0160] 4) Growth of LED epitaxial wafer on MO source coating layer

[0161] ①The sapphire substrate with the TMG source mixed precursor coating layer of the dispersed Al2O3 nanoparticles is placed in the MOCVD reaction chamber, the pressure is set to 200 torr, the TMG source is introduced, the temperature is set to 1200°C, NH3 and H2 are introduced for annealing recrystallization for 30 s, the flow ratio of NH3 and H2 is 100:1, and a GaN stress release buffer layer 2 is prepared;

[0162] ②Under the conditions of a temperature of 1080°C and a growth pressure of 200 torr, a non-intentionally doped nitride layer 3 with a thickness of 3 μm is grown on the GaN stress release buffer layer 2, which is a non-intentionally doped GaN layer, the required Ga source is a TMG source, and the growth atmosphere is an H2 atmosphere;

[0163] ③Under the conditions of a temperature of 1060°C and a growth pressure of 200 torr, an n-type nitride layer 4 with a thickness of 3 μm is grown on the non-intentionally doped nitride layer 3, which is an n-type GaN layer, the doping concentration of Si is 8×10 18 cm -3 , the required Ga source for growth is a TMG source, and the growth atmosphere is an H2 atmosphere;

[0164] ④On the n-type nitride layer 4, a light-emitting layer 5 is grown, which is a repeated growth of 6 pairs of InGaN / GaN multi-quantum well light-emitting layers, the thickness of the InGaN quantum well layer 51 is 3 nm, the growth temperature is 730°C, the growth atmosphere is switched to an N2 atmosphere, the growth pressure is 400 torr, the thickness of the GaN quantum barrier layer 52 is 11 nm, the growth temperature is 805°C, the growth atmosphere is switched to an H2 atmosphere, the growth pressure is 400 torr, and the required Ga source for growth is a TEGa source, and the In source is a TMIn source;

[0165] ⑤On the InGaN / GaN multi-quantum well light-emitting layer 5, under the conditions of a temperature of 1050 DEG C and a growth pressure of 100 torr, an electron blocking layer 6 with a thickness of 150 nm is grown, which is a p-type AlGaN electron blocking layer, the Ga source required for growth is a TMG source, the Al source is TMAl, and the growth atmosphere is an N2 atmosphere;

[0166] ⑥On the electron blocking layer 6, under the conditions of a temperature of 1050 DEG C and a growth pressure of 200 torr, a p-type nitride layer 7 with a thickness of 200 nm is grown, which is a p-type GaN layer, the Mg doping concentration is 5*10 19 cm -3 , the Ga source required for growth is a TMG source, and the growth atmosphere is switched to an H2 atmosphere.

[0167] After testing, the LED epitaxial wafer obtained in this embodiment emits 470 nm blue light with a half peak width of 18.5 nm, a wavelength uniformity std of 0.98 nm, a surface defect of 2*10 8 cm -2 By spin-coating different uniformly dispersed graphene nanoparticle TMG source precursor layers as stress release buffer layers, stress release can reduce dislocation density and residual stress, improve quantum well light-emitting layer growth quality, improve leakage performance and light-emitting efficiency, and at the same time improve light-emitting wavelength uniformity, which can meet the uniform performance requirements of Micro-LED epitaxy.

[0168] Embodiment 6

[0169] 1) Preparation of graphene dispersion

[0170] Anhydrous ethanol is used, 5% by mass fraction of graphene nanopowder with a diameter of 300-500 nm is added, and 0.15% by mass fraction of citric acid dispersant is added, and ultrasonic treatment is performed at room temperature for 30 min;

[0171] 2) Preparation of graphene nanoparticle TMG source

[0172] The graphene nanoparticles are separated from the solvent, quickly dried, and immediately mixed with high-purity TMG source, the mass fraction of graphene nanoparticles is 5%, ultrasonic treatment is performed at 25 DEG C for 45 min, and a uniformly dispersed graphene nanoparticle TMG source mixed precursor is obtained;

[0173] 3) Spin-coating of graphene nanoparticle TMG source mixed precursor

[0174] In a glove box N2 atmosphere, the graphene nanoparticle TMG source mixed precursor is spin-coated on the sapphire substrate by a spin coater at a speed of 4000 rpm, and a uniformly dispersed graphene nanoparticle TMG source mixed precursor coating layer with a thickness of 2000 nm is formed on the substrate;

[0175] 4) LED epitaxial wafer growth on MO source coating layer

[0176] ① Put the sapphire substrate with the TMG source mixed precursor coating layer with dispersed graphene nanoparticles into the MOCVD reaction chamber, set the pressure to 100 torr, input the TMG source, set the temperature to 1200℃, input NH3 and H2 to anneal and recrystallize for 100s, the flow ratio of NH3 and H2 is 50:1, and obtain a GaN stress release buffer layer 2;

[0177] ② Grow a 3μm-thick unintentionally doped nitride layer 3 on the GaN stress release buffer layer 2 under the conditions of a temperature of 1080℃ and a growth pressure of 200 torr, the unintentionally doped nitride layer 3 is an unintentionally doped GaN layer, the required Ga source is a TMG source, and the growth atmosphere is an H2 atmosphere;

[0178] ③ Grow a 3μm-thick n-type nitride layer 4 on the unintentionally doped nitride layer 3 under the conditions of a temperature of 1060℃ and a growth pressure of 200 torr, the n-type nitride layer 4 is an n-type GaN layer, the Si doping concentration is 8×10 18 cm -3 , the required Ga source for growth is a TMG source, and the growth atmosphere is an H2 atmosphere;

[0179] ④ Grow a light-emitting layer 5 on the n-type nitride layer 4, which is a 10-pair InGaN / GaN multiple quantum well light-emitting layer, the thickness of the InGaN quantum well layer 51 is 6nm, the growth temperature is 800℃, the growth atmosphere is switched to an N2 atmosphere, the growth pressure is 200 torr, the thickness of the GaN quantum barrier layer 52 is 6nm, the growth temperature is 900℃, the growth atmosphere is switched to an H2 atmosphere, the growth pressure is 200 torr, the required Ga source for growth is a TEGa source, and the In source is a TMIn source;

[0180] ⑤ Grow a 25nm-thick electron blocking layer 6 on the InGaN / GaN multiple quantum well light-emitting layer 5 under the conditions of a temperature of 950℃ and a growth pressure of 200 torr, the electron blocking layer 6 is a p-type AlGaN electron blocking layer, the required Ga source for growth is a TMG source, the Al source is a TMAl source, and the growth atmosphere is an N2 atmosphere;

[0181] ⑥ Grow a 50nm-thick p-type nitride layer 7 on the electron blocking layer 6 under the conditions of a temperature of 950℃ and a growth pressure of 600 torr, the p-type nitride layer 7 is a p-type GaN layer, the Mg doping concentration is 5×10 19 cm -3 , the required Ga source for growth is a TMG source, and the growth atmosphere is switched to an H2 atmosphere.

[0182] Example 7

[0183] 1) Preparation of TiO2 nanoparticle dispersion

[0184] Anhydrous ethanol was used, 30% by mass of TiO2 nanopowder with a diameter of 30-80 nm was added, 0.15% by mass of citric acid dispersant was added, and ultrasonic treatment was performed at room temperature for 2 hours;

[0185] 2) Preparation of TiO2 nanoparticle TMG source

[0186] The TiO2 nanoparticles were separated from the solvent, quickly dried, and immediately mixed with a high-purity TMG source, the mass fraction of TiO2 nanoparticles was 28%, and ultrasonic treatment was performed at 5°C for 50 minutes to obtain a uniformly dispersed TiO2 nanoparticle TMG source mixed precursor;

[0187] 3) Spin coating of TiO2 nanoparticle TMG source mixed precursor

[0188] In a glove box under N2 atmosphere, the TiO2 nanoparticle TMG source mixed precursor was spin-coated on a sapphire substrate at a speed of 4000 rpm using a spin coater, and a uniformly dispersed TiO2 nanoparticle TMG source mixed precursor coating layer with a thickness of 2000 nm was formed on the substrate;

[0189] 4) Growth of LED epitaxial wafer on MO source coating layer

[0190] ① The sapphire substrate with the TMG source mixed precursor coating layer with dispersed TiO2 nanoparticles was placed in the MOCVD reaction chamber, the pressure was set to 600 torr, the TMG source was introduced, the temperature was set to 1200°C, NH3 and H2 were introduced for annealing and recrystallization for 100 seconds, the flow ratio of NH3 and H2 was 30:1, and a GaN stress release buffer layer 2 was prepared;

[0191] The remaining steps are the same as in Example 6.

[0192] Example 5 and Example 6 prepared ultraviolet epitaxial wafers with wavelengths of 400 nm and 415 nm, respectively, the LED epitaxial wafer photoluminescence PL test wavelength uniformity std was 0.52 and 0.65 nm, the half peak width was less than 15 nm, the surface defect was 2.2×10 8 cm -2 , and the surface roughness Ra of the epitaxial wafer was less than 0.7.

[0193] The inventors of the present application also spin-coat a TMG source precursor layer of different uniformly dispersed metal oxide nanoparticles (such as ZnO, Fe3O4, Ta2O5, SnO2, ZrO2, etc.) as a stress release buffer layer, which can reduce dislocation density and residual stress, improve quantum well light-emitting layer growth quality, improve leakage performance and light-emitting efficiency, and improve light-emitting wavelength uniformity, and can meet the uniform performance requirements of Micro-LED epitaxy.

[0194] Example 8

[0195] 1) Preparation of GaN nanoparticle dispersion liquid

[0196] Anhydrous ethanol is added, 30% by mass of GaN nanopowder with a diameter of 30-80 nm is added, and 0.15% by mass of citric acid dispersant is added, and ultrasonic treatment is performed at room temperature for 2 h;

[0197] 2) Preparation of GaN nanoparticle TMG source

[0198] The GaN nanoparticles are separated from the solvent, and immediately mixed with a high-purity TMG source after rapid drying, the mass fraction of the GaN nanoparticles is 24%, and ultrasonic treatment is performed at 5°C for 50 min to obtain a TMG source mixed precursor of uniformly dispersed GaN nanoparticles;

[0199] 3) Spin-coating of GaN nanoparticle TMG source mixed precursor

[0200] In a glove box under N2 atmosphere, the GaN nanoparticle TMG source mixed precursor is spin-coated on a sapphire substrate by a spin coater at a speed of 4000 rpm to form a TMG source mixed precursor coating layer of uniformly dispersed GaN nanoparticles with a thickness of 2000 nm on the substrate;

[0201] 4) Growth of LED epitaxial wafer on MO source coating layer

[0202] ①The sapphire substrate with the TMG source mixed precursor coating layer of uniformly dispersed GaN nanoparticles is placed in a MOCVD reaction chamber, the pressure is set to 300 torr, the TMG source is introduced, the temperature is set to 1200°C, and NH3 and H2 are introduced for annealing and recrystallization for 100 s, the flow ratio of NH3 and H2 is 60:1, and a GaN stress release buffer layer 2 is prepared;

[0203] The remaining steps are the same as those in Example 6.

[0204] Example 9

[0205] 1) Preparation of Si dispersion liquid

[0206] Anhydrous ethanol is used, 5% by mass of Si nanopowder with a diameter of 5000-800 nm is added, 0.15% by mass of citric acid dispersant is added, and ultrasonic treatment is performed at room temperature for 30 min;

[0207] 2) Preparation of Si nanoparticle TMG source

[0208] The Si nanoparticles are separated from the solvent, quickly dried, immediately mixed with a high-purity TMG source, the mass fraction of Si nanoparticles is 5%, ultrasonic treatment is performed at 25°C for 10 min, and a TMG source mixed precursor with uniformly dispersed Si nanoparticles is obtained;

[0209] 3) Spin coating of Si nanoparticle TMG source mixed precursor

[0210] In a glove box under N2 atmosphere, the Si nanoparticle TMG source mixed precursor is spin coated on a sapphire substrate at a speed of 4000 rpm by using a spin coater, and a TMG source mixed precursor coating layer with uniformly dispersed Si nanoparticles with a thickness of 2000 nm is formed on the substrate;

[0211] 4) Growth of LED epitaxial wafer on MO source coating layer

[0212] ①The sapphire substrate with the TMG source mixed precursor coating layer with dispersed Si nanoparticles is placed in a MOCVD reaction chamber, the pressure is set to 500 torr, the TMG source is introduced, the temperature is set to 1125°C, NH3 and H2 are introduced for annealing and recrystallization for 10 s, the flow ratio of NH3 and H2 is 100:1, and GaN stress release buffer layer 2 is prepared;

[0213] The remaining steps are the same as in Example 6.

[0214] The inventors of the present case also spin-coat different TMG source precursor layers of uniformly dispersed non-metallic nanoparticles (such as C, SiC, B4C, BN, etc.) as stress release buffer layers, which can reduce dislocation density and residual stress, improve the growth quality of quantum well light-emitting layer, improve the leakage performance and light-emitting efficiency, and at the same time improve the uniformity of light-emitting wavelength (std < 1 nm), the particle density on the epitaxial wafer surface is less than 10, and the defect density is less than 5×10 8 cm -2 , which can meet the uniform performance requirements of Micro-LED epitaxy.

[0215] Correspondingly, the inventors of the present case also spin-coat a TMG source precursor layer of uniformly dispersed organic compound nanoparticles, such as polystyrene, as a buffer layer, and the test results are basically the same as the foregoing examples.

[0216] Example 10

[0217] 1) Preparation of Ni nanoparticle dispersion

[0218] Anhydrous ethanol was used, 30% by mass of Ni nanopowder with a diameter of 30-80 nm was added, and 0.15% by mass of citric acid dispersant was added, and ultrasonic treatment was carried out at room temperature for 2 hours;

[0219] 2) Preparation of Ni nanoparticle TMG source

[0220] The Ni nanoparticles were separated from the solvent, and immediately mixed with a high-purity TMG source, with a mass fraction of 40% of the Ni nanoparticles, and ultrasonic treatment was carried out at 40°C for 30 minutes to obtain a uniformly dispersed TMG source mixed precursor of the Ni nanoparticles;

[0221] 3) Spin coating of the Ni nanoparticle TMG source mixed precursor

[0222] In a glove box under a N2 atmosphere, the Ni nanoparticle TMG source mixed precursor was spin coated on a silicon substrate using a spin coater at a speed of 4000 rpm to form a TMG source mixed precursor coating layer of the Ni nanoparticles with a uniform dispersion on the substrate, with a thickness of 25 nm;

[0223] 4) Growth of an LED epitaxial wafer on a Group III metal organic source coating layer

[0224] ①The silicon substrate with the TMG source mixed precursor coating layer of the Ni nanoparticles was placed in a MOCVD reaction chamber, the pressure was set to 200 torr, the TMG source was introduced, the temperature was set to 650°C, and annealing recrystallization was carried out for 10 seconds using AsH3 and H2, with a flow ratio of AsH3 to H2 of 15:1, to obtain a GaAs s stress release buffer layer 2;

[0225] ②On the GaAs s stress release buffer layer 2, a 3 μm thick unintentionally doped nitride layer 3 was grown at a temperature of 1200°C and a growth pressure of 100 torr, which was an unintentionally doped GaN layer, the Ga source required for growth was a TMG source, and the growth atmosphere was an H2 atmosphere;

[0226] ③On the unintentionally doped nitride layer 3, a 3 μm thick n-type nitride layer 4 was grown at a temperature of 1000°C and a growth pressure of 600 torr, which was an n-type GaN layer, the Si doping concentration was 8×10 18 Gm -3 , the Ga source required for growth was a TMG source, and the growth atmosphere was an H2 atmosphere;

[0227] (4) On the n-type nitride layer 4, a light emitting layer 5 is grown, which is a pair of InGaN / GaN multiple quantum well light emitting layers 6 repeatedly grown, the thickness of the InGaN quantum well layer 51 is 3 nm, the growth temperature is 750°C, the growth atmosphere is switched to N2 atmosphere, the growth pressure is 500 torr, the thickness of the GaN quantum barrier layer 52 is 11 nm, the growth temperature is 810°C, the growth atmosphere is switched to H2 atmosphere, the growth pressure is 500 torr, the Ga source required for growth is TEGa, and the In source is TMIn;

[0228] (5) On the InGaN / GaN multiple quantum well light emitting layer 5, an electron blocking layer 6 is grown, which is a p-type AlGaN electron blocking layer with a thickness of 25 nm, the growth temperature is 850°C, the growth pressure is 200 torr, the Ga source required for growth is TMG source, the Al source is TMAl, and the growth atmosphere is N2 atmosphere;

[0229] (6) On the electron blocking layer 6, a p-type nitride layer 7 is grown, which is a p-type GaN layer with a thickness of 50 nm, the Mg doping concentration is 5×1019cm-3, the growth temperature is 950°C, the growth pressure is 200 torr, the Ga source required for growth is TMG source, and the growth atmosphere is switched to H2 atmosphere. 19 cm -3

[0230] Example 11

[0231] 1) Preparation of Ni nanoparticle dispersion

[0232] Anhydrous ethanol is used, 30% by mass of Ni powder with a diameter of 30-80 nm is added, and 0.15% by mass of citric acid dispersant is added, and ultrasonic treatment is performed at room temperature for 2 hours;

[0233] 2) Preparation of Ni nanoparticle dimethyl ethyl indium

[0234] The Ni nanoparticles are separated from the solvent, and immediately after rapid drying, the Ni nanoparticles are mixed with a high-purity dimethyl ethyl indium source, the mass fraction of the Ni nanoparticles is 40%, ultrasonic treatment is performed at 40°C for 30 minutes, and a uniformly dispersed dimethyl ethyl indium source mixed precursor of Ni nanoparticles is obtained;

[0235] 3) Spin coating of Ni nanoparticle trimethyl indium source mixed precursor

[0236] In a glove box under N2 atmosphere, the Ni nanoparticle dimethyl ethyl indium source mixed precursor is spin coated on a silicon substrate at a speed of 4000 rpm by using a spin coater, and a uniformly dispersed dimethyl ethyl indium source mixed precursor coating layer of Ni nanoparticles with a thickness of 20 nm is formed on the substrate;

[0237] 4) Growth of LED epitaxial wafer on III metal organic source coating layer​

[0238] ①The GaAs substrate with a coating layer of dimethyl ethyl indium source mixed precursor with dispersed Ni nanoparticles is placed in the MOCVD reaction chamber, the pressure is set to 400 torr, the temperature is set to 500 °C, and the tertiary butyl arsenic (TBA) and H2 are annealed and recrystallized for 10 s, the flow ratio of TBA and H2 is 15:1, and dimethyl ethyl indium is introduced to obtain an InAs stress release buffer layer 2;

[0239] ②On the InAs stress release buffer layer 2, a non-intentionally doped nitride layer 3 with a thickness of 3 μm is grown under the conditions of a temperature of 1000 °C and a growth pressure of 600 torr, which is a non-intentionally doped GaN layer, the required Ga source is a TMG source, and the growth atmosphere is an H2 atmosphere;

[0240] ③On the non-intentionally doped nitride layer 3, an n-type nitride layer 4 with a thickness of 3 μm is grown under the conditions of a temperature of 1200 °C and a growth pressure of 100 torr, which is an n-type GaN layer, the Si doping concentration is 8×10 18 cm -3 , the required Ga source for growth is a TMG source, and the growth atmosphere is an H2 atmosphere;

[0241] ④On the n-type nitride layer 4, a light-emitting layer 5 is grown, which is a light-emitting layer of 6 pairs of InGaN / GaN multiple quantum wells, the thickness of the InGaN quantum well layer 51 is 2 nm, the growth temperature is 700 °C, the growth atmosphere is switched to an N2 atmosphere, the growth pressure is 200 torr, the thickness of the GaN quantum barrier layer 52 is 20 nm, the growth temperature is 950 °C, the growth atmosphere is switched to an H2 atmosphere, the growth pressure is 200 torr, the required Ga source for growth is TEGa, and the In source is TMIn;

[0242] ⑤On the InGaN / GaN multiple quantum well light-emitting layer 5, an electron blocking layer 6 with a thickness of 25 nm is grown under the conditions of a temperature of 950 °C and a growth pressure of 200 torr, which is a p-type AlGaN electron blocking layer, the required Ga source for growth is a TMG source, the Al source is TMAl, and the growth atmosphere is an N2 atmosphere;

[0243] ⑥On the electron blocking layer 6, a p-type nitride layer 7 with a thickness of 50 nm is grown under the conditions of a temperature of 950 °C and a growth pressure of 200 torr, which is a p-type GaN layer, the Mg doping concentration is 5×10 19 cm -3 , the required Ga source for growth is a TMG source, and the growth atmosphere is switched to an H2 atmosphere.

[0244] Example 12

[0245] 1) Preparation of Ni nanoparticle dispersion

[0246] Anhydrous ethanol was used, 30% by mass of Ni nanoparticles with a diameter of 30-80 nm was added, 0.15% by mass of citric acid dispersant was added, and ultrasonic treatment was performed at room temperature for 2 hours;

[0247] 2) Preparation of Ni nanoparticle dimethyl ethyl indium

[0248] The Ni nanoparticles were separated from the solvent, and immediately mixed with high-purity dimethyl ethyl indium, the mass fraction of the Ni nanoparticles was 40%, ultrasonic treatment was performed at 20°C for 30 minutes, and a uniformly dispersed Ni nanoparticle dimethyl ethyl indium source mixed precursor was obtained;

[0249] 3) Spin coating of the Ni nanoparticle dimethyl ethyl indium mixed precursor

[0250] In a glove box under N2 atmosphere, the Ni nanoparticle dimethyl ethyl indium source mixed precursor was spin coated on a silicon substrate by using a spin coater at a rotation speed of 4000 rpm, and a uniformly dispersed Ni nanoparticle dimethyl ethyl indium source mixed precursor coating layer with a thickness of 100 nm was formed on the substrate;

[0251] 4) Growth of the III metal organic source coating layer on the LED epitaxial wafer

[0252] ①The GaAs substrate with the uniformly dispersed Ni nanoparticle dimethyl ethyl indium source mixed precursor coating layer was placed in a MOCVD reaction chamber, the pressure was set to 500 torr, dimethyl ethyl indium was introduced, the temperature was set to 650°C, and a stress release buffer layer 2 of InP was prepared by introducing tertiary butyl phosphine (TBP) and H2 for annealing and recrystallization for 100 seconds, the flow ratio of TBP and H2 was 20:1;

[0253] The remaining steps were the same as in Example 11.

[0254] The above Examples 10, 11 and 12 prepared nitride LED epitaxial layers on GaAs substrates by spin coating different uniformly dispersed metal nanoparticle source mixed precursor layers as stress release buffer layers. Since the GaAs substrate has high quality, is easy to cleave, and is low in price, the process is mature, and the practicability of GaAs substrate nitride materials is expanded. In addition, GaAs is easy to be doped with p-type to improve light emission efficiency. Compared with the nitride LED prepared by using the conventional buffer layer method on the GaAs substrate, the intensity of the epitaxial PL test is increased by more than 10 times, and the intensity of the electroluminescence under the condition of 20 mA is increased by more than 6 times.

[0255] Example 13

[0256] 1) Preparation of Ni nanoparticle dispersion

[0257] The anhydrous ethanol is used, the mass fraction of 30% of the diameter of 30-80nm of the nano-Ni powder is added, the mass fraction of 0.15% of the citric acid dispersant is added, and the ultrasonic is performed for 2h at room temperature;

[0258] 2) Preparation of the Ni nanoparticle trimethylaluminum source

[0259] The Ni nanoparticles are separated from the solvent, and are quickly dried to be mixed with the high-purity trimethylaluminum source immediately, the mass fraction of the Ni nanoparticles is 45%, and the ultrasonic is performed for 40min at 40℃ to obtain the trimethylaluminum source mixed precursor of the uniformly dispersed Ni nanoparticles;

[0260] 3) Spin coating of the Ni nanoparticle trimethylaluminum source mixed precursor

[0261] In the glove box N2 atmosphere, the spin coating method of the film applicator is used to spin coat the Ni nanoparticle trimethylaluminum source mixed precursor on the sapphire substrate at the rotating speed of 4000rpm, and the trimethylaluminum source mixed precursor coating layer of the uniformly dispersed Ni nanoparticles with the thickness of 60nm is formed on the substrate;

[0262] 4) Growth of the LED epitaxial wafer on the III group metal organic source coating layer

[0263] ①The sapphire substrate with the trimethylaluminum source mixed precursor coating layer of the dispersed Ni nanoparticles is placed in the MOCVD reaction chamber, the pressure is set to be 100torr, the trimethylaluminum source is input, the temperature is set to be 1200℃, the NH3 and H2 are input to anneal and recrystallize for 10s, the flow ratio of the NH3 and H2 is 50:1, and the AlN stress release buffer layer 2 is prepared;

[0264] The remaining steps are the same as those in Example 11.

[0265] Comparative Example 1

[0266] The difference between the present comparative example and Example 1 is that the Ni nanoparticles are not added in the TMG source.

[0267] The surface roughness Ra of the epitaxial wafer obtained in the present comparative example is 0.8, the thickness uniformity of the epitaxial layer is 2.5%, the photoluminescence PL test of the blue light wave half peak width at 470nm is 20nm, the wavelength uniformity std is 1.5nm, and the surface defect of the epitaxial wafer is 7×10 8 cm -2 The point test brightness of the electroluminescence is 125, and the point test voltage is 5.2V.

[0268] Comparative Example 2

[0269] The difference between the present comparative example and Example 1 is that the TMG source spin coating is not used, and the GaN buffer layer is directly grown by the conventional MOCVD epitaxy.

[0270] The surface roughness Ra of the epitaxial wafer obtained in the present comparative example is 1, the thickness uniformity of the epitaxial layer is 3%, the photoluminescence PL test 470nm blue light wave half-width is 22nm, the wavelength uniformity std is 2nm, the surface defect of the epitaxial wafer is 8x10 8 cm -2 , the electroluminescence point test brightness is 118, and the point test voltage is 5.9V.

[0271] The final LED chip test of the same size of the present embodiment 1, the comparative example 1 and the comparative example 2 shows that the brightness of the present embodiment 1 is improved by more than 2% compared with the comparative example 1, and the leakage IR yield is improved by 4%. See Table 1 for results.

[0272] Table 1

[0273]

[0274]

[0275] Therefore, the present application provides nucleation centers by gradually forming two kinds of crystal nucleus distribution through spin coating different uniform dispersed metal nanoparticle coating layers and combining MOCVD reaction cavity annealing recrystallization, gradually releases the stress of the epitaxial layer, strengthens the lateral epitaxial growth, inhibits the extension of the dislocation density of the epitaxial layer, reduces the defect density, improves the growth quality of the quantum well light-emitting layer, improves the leakage performance and light-emitting efficiency, and improves the uniformity of the light-emitting wavelength, which can meet the uniform performance requirements of Micro-LED epitaxial wafers.

[0276] It should be understood that the LED epitaxial wafer preparation method in the present application is not limited to the above-mentioned embodiments, and the above-mentioned embodiments are a preferred embodiment of the present application, but as long as the spin coating nanoparticle precursor epitaxial growth bottom layer structure belongs to the scope protected by the present application.

[0277] It is obvious to those skilled in the art that the present application is not limited to the details of the above exemplary embodiments, and the present application can be implemented in other specific forms without departing from the spirit or essential characteristics of the present application. Therefore, the embodiments should be regarded as exemplary and non-limiting in any respect, and the scope of the present application is defined by the appended claims rather than the above description, and therefore all expressions of words and phrases contained in the claims are intended to be included in the present application. Any reference signs in the claims should not be regarded as limiting the claims.

Claims

1. A method of producing a high-quality semiconductor epitaxial wafer, characterized by, The application relates to a stress release buffer layer and a preparation method thereof. The nanomaterial is uniformly mixed with a III-group metal organic source, and ultrasonic treatment is carried out at 5-40 DEG C for 10-60 min to obtain a III-group metal organic source mixed precursor containing uniformly dispersed nanomaterials; The III-group metal organic source mixed precursor is coated on a substrate (1) to obtain a III-group metal organic source mixed precursor coating layer, and then the substrate with the III-group metal organic source mixed precursor coating layer is placed in a MOCVD reaction chamber, a III-group metal organic source is introduced, the reaction chamber is heated to 500-1200 DEG C, annealing recrystallization is carried out in a mixed atmosphere of a V-group element source and a reducing gas, thereby forming uniformly distributed nanomaterials and III-V compound nano growth structures, and a stress release buffer layer (2) is obtained; A semiconductor epitaxial structure is grown on the stress release buffer layer (2) to obtain a high-quality semiconductor epitaxial wafer.

2. The method of claim 1, wherein: The nanomaterials include any one or a combination of zero-dimensional nanomaterials, one-dimensional nanomaterials, two-dimensional nanomaterials and three-dimensional nanomaterials; and / or the morphology of the nanomaterials includes any one or a combination of two or more of nanoparticle, nanowire, nanofilm and nanobulk; and / or the nanomaterials include any one or a combination of two or more of metal nanomaterials, non-metal inorganic nanomaterials and organic compound nanomaterials.

3. The method of claim 1, wherein: The mass ratio of the nanomaterials to the III-group metal organic source in the mixed precursor is less than 1:

1.

4. The method of claim 2, wherein: The nanomaterials include any one or a combination of two or more of Si3N4, SiO2, GaN, AlN, InN, SiC, ScAlN, Al2O3, Si, C, TiC, TiN, WC, WC-Co, B4C, BN, TiB2, LaF3, MoS2, ZrB2, ZnS, ZnSe, ZnO, Fe3O4, Ta2O5, SnO2, TiO2, ZrO2, Ni, Au, Ag, Fe, Co, Mn, Ti, Mg, Al, Ga, In, perovskite and graphene.

5. The method of claim 2, wherein: The diameter of the nanomaterials is 5-500 nm.

6. The method of claim 4, wherein: The nanomaterials include any one or a combination of two or more of Si3N4, SiO2, GaN, AlN, InN, SiC, ScAlN, Al2O3, Si, TiC, TiN, BN, ZnS, ZnSe, ZnO, TiO2, Ni, Au, Ag, Fe, Co, Mn, Ti, Mg, Al and graphene.

7. The method of claim 4, wherein: The nanomaterials include any one or a combination of two or more of Si3N4, SiO2, GaN, AlN, SiC, ScAlN, Al2O3, TiO2, Ni, Al, Ga and graphene.

8. The method of claim 1, wherein: The III group element contained in the III group metal organic source includes any one or more than two combinations of indium, gallium and aluminum; the III group metal organic source includes a III group organic compound source, and the III group organic compound source includes any one or more than two combinations of an indium source, a gallium source and an aluminum source; the indium source includes any one or more than two combinations of trimethyl indium, triethyl indium and dimethyl ethyl indium, the gallium source includes any one or more than two combinations of trimethyl gallium, triethyl gallium and triisopropyl gallium, and the aluminum source includes any one or more than two combinations of trimethyl aluminum, triethyl aluminum, dimethyl aluminum, dimethyl aluminum hydride and aluminum hydride complex.

9. The method of claim 1, wherein: The V group element source contains V group elements including any one or more than two combinations of nitrogen, phosphorus and arsenic; the V group element source includes any one or more than two combinations of a nitrogen source, a phosphorus source and an arsenic source; the nitrogen source includes any one or more than two combinations of NH3, an organic amine compound and a trap compound; the organic amine compound includes an alkyl amine, and the alkyl amine includes t-butyl amine and / or n-propyl amine; the trap compound includes dimethyl trap; the phosphorus source includes PH3 and / or an organic phosphorus source, and the organic phosphorus source includes t-butyl phosphorus; the arsenic source includes AsH3 and / or an organic arsenic source, and the organic arsenic source includes t-butyl arsenic. The reducing gas includes H2.

10. The method of claim 1, wherein: The flow ratio of the V group element source to the reducing gas in the mixed atmosphere is 10:1 to 100:

1.

11. The method of claim 1, wherein: Further comprising:

12. The method of claim 1, wherein, A non-intentionally doped nitride layer (3), an n-type nitride layer (4), a light emitting layer (5), an electron blocking layer (6) and a p-type nitride layer (7) are sequentially grown on the stress release buffer layer (2) to obtain a high-quality semiconductor epitaxial wafer. Comprising the following steps:

13. The method of claim 12, wherein, 1) providing a substrate (1), wherein the substrate (1) is sapphire, silicon carbide, silicon, zinc oxide, gallium nitride or gallium arsenide; 2) coating the III group metal organic source mixed precursor on the substrate (1) by using a spin coating method in a N2 atmosphere to form a III group metal organic source mixed precursor coating layer with a thickness of 20nm to 2000nm on the substrate (1); 3) placing the substrate with the III group metal organic source mixed precursor coating layer into a reaction chamber of a MOCVD growth device, the pressure in the reaction chamber is 100 to 600torr, a III group metal organic source is introduced, the III group metal organic source is a III group organic compound source, the reaction chamber is heated to 500 to 1200℃, a V group element source and a reducing gas are introduced for annealing recrystallization for 10s to 100s, and then a stress release buffer layer (2) with a thickness of 10 to 100nm is grown; 4) growing a non-intentionally doped nitride layer (3) on the stress release buffer layer (2), wherein the non-intentionally doped nitride layer (3) is a non-intentionally doped GaN layer, the Ga source required for growth is a TMG source, the growth atmosphere is a H2 atmosphere, the growth temperature is 1000 to 1200℃, and the growth pressure is 100 to 600torr; ​ 5) An n-type nitride layer (4) is grown on the unintentionally doped nitride layer (3), wherein the n-type nitride layer (4) is an n-type GaN layer and the Si doping concentration is 2×10⁻⁶. 18 cm -3 ~5×10 19 cm -3 The Ga source required for growth is TMG source, the growth atmosphere is H2 atmosphere, the growth temperature is 1000~1200℃, and the growth pressure is 100~600 torr. 6) growing a light-emitting layer (5) on the n-type nitride layer (4), 1-20 pairs of InGaN / GaN multi-quantum well light-emitting layers are co-grown, the InGaN / GaN multi-quantum well light-emitting layer comprises periodically and alternately grown InGaN quantum well layers (51) and GaN quantum barrier layers (52), the thickness of the InGaN quantum well layer (51) is 2-6 nm, the Ga source required for growth is a TEG source, the In source is a TMIn source, the growth atmosphere is an N2 atmosphere, the growth temperature is 700-900°C, and the growth pressure is 200-500 torr; the thickness of the GaN quantum barrier layer (52) is 6-20 nm, the Ga source required for growth is a TEG source, the growth atmosphere is an H2 atmosphere, the growth temperature is 750-950°C, and the growth pressure is 200-500 torr; 7) growing an electron blocking layer (6) on the light-emitting layer (5), the electron blocking layer (6) is a p-type AlGaN electron blocking layer, the Ga source required for growth is a TMG source, the Al source is a TMAl source, the growth atmosphere is an N2 atmosphere, the growth temperature is 950-1050°C, and the growth pressure is 100-200 torr; 8) A p-type nitride layer (7) is grown on the electron blocking layer (6), wherein the p-type nitride layer (7) is a p-type GaN layer and the Mg doping concentration is 1×10⁻⁶. 18 cm -3 ~5×10 20 cm -3 The Ga source required for growth is TMG source, the growth atmosphere is H2 atmosphere, the growth temperature is 950~1050℃, and the growth pressure is 200~600 torr.

14. High-quality semiconductor epiwafer produced by the method according to any one of claims 1 to 13, comprising a substrate (1), characterized in that: The substrate (1) has a stress release buffer layer (2) and a semiconductor epitaxial structure formed in sequence thereon; wherein the stress release buffer layer (2) is formed by an annealing recrystallization of a III metal organic source mixed precursor coating layer coated on the surface of the substrate (1).

15. The high-quality semiconductor epitaxial wafer of claim 14, wherein: The high-quality semiconductor epitaxial wafer is a light-emitting diode epitaxial wafer, which comprises a substrate (1) and a stress release buffer layer (2), a non-intentionally doped nitride layer (3), an n-type nitride layer (4), a light-emitting layer (5), an electron blocking layer (6), and a p-type nitride layer (7) formed in sequence on the substrate (1).

16. The high-quality semiconductor epitaxial wafer of claim 15, wherein: The non-intentionally doped nitride layer (3) is a non-intentionally doped GaN layer with a thickness of 1-4 µm.

17. The high-quality semiconductor epiwafer of claim 15, wherein: The n-type nitride layer (4) is an n-type GaN layer with a thickness of 1-4 pm, and the doping concentration of Si is 2x10 18 cm -3 ~5x10 19 cm -3 .

18. The high-quality semiconductor epitaxial wafer of claim 15, wherein: The light-emitting layer (5) is an InGaN / GaN multi-quantum well light-emitting layer, which comprises periodically and alternately grown InGaN quantum well layers (51) and GaN quantum barrier layers (52), and the repeating period is 1-20, the thickness of the InGaN quantum well layer (51) is 2-6 nm, and the thickness of the GaN quantum barrier layer (52) is 6-20 nm.

19. The high-quality semiconductor epitaxial wafer of claim 15, wherein: The electron blocking layer (6) is a p-type AlGaN electron blocking layer with a thickness of 15-150 nm.

20. The high-quality semiconductor epitaxial wafer of claim 15, wherein: The p-type nitride layer (7) is a p-type GaN layer with a thickness of 20-200 nm, and the doping concentration of Mg is 1 x 1018-5 x 1019 cm-3. 18 cm -3 ~5 x 1019 20 cm -3 .

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