High hydrolysis resistance blue-green LED epitaxial wafer structure and preparation method thereof

Abstract

The present invention discloses a blue-green LED epitaxial wafer structure with high hydrolysis resistance and a method for preparing the same, relating to the fields of semiconductor optoelectronic devices and semiconductor lighting manufacturing. The epitaxial structure preparation method comprises providing a substrate, and separately growing a buffer layer, a u-GaN layer, a first n-GaN layer, an n-AlGaN layer, a second n-GaN layer, an InGaN / GaN layer, a quantum well layer, a first p-GaN layer, a p-AlGaN layer, and a second p-GaN layer, thereby obtaining a blue-green LED epitaxial wafer with high hydrolysis resistance. Implementation of the present invention can improve the quality of the epitaxial crystals and the compactness of the epitaxial layers, thereby enhancing hydrolysis resistance.

Description

Technical Field

[0001] The present invention relates to the field of semiconductor optoelectronic devices and semiconductor lighting manufacturing, and in particular to a method for preparing a blue-green LED epitaxial wafer with high hydrolysis resistance. Background Art

[0002] In recent years, the performance of light-emitting diodes (LEDs) has significantly improved, leading to widespread application in indoor and outdoor lighting, automotive lighting, display backlights, and microelectronics. However, during their use, LEDs must withstand the damage caused by high temperatures and high humidity environments. Consequently, hydrolysis resistance is a key requirement for LED epitaxial wafers and chips.

[0003] In the prior art, a protective structure is generally added to the sidewall of the chip, or an anti-hydrolysis groove is formed on the top of the chip by etching to prevent water vapor from climbing up. However, these methods require increasing the LED manufacturing process and reduce production efficiency. Summary of the Invention

[0004] The technical problem to be solved by the present invention is to provide a method for preparing a blue-green light LED epitaxial wafer structure with high hydrolysis resistance, wherein the epitaxial wafer prepared can effectively improve the hydrolysis resistance of the blue-green light LED chip.

[0005] The technical problem that the present invention also aims to solve is to provide a blue-green LED epitaxial wafer with high hydrolysis resistance.

[0006] Another technical problem to be solved by the present invention is to provide a blue-green LED with high hydrolysis resistance.

[0007] In order to solve the above problems, the present invention discloses a method for preparing a blue-green LED epitaxial wafer structure with high hydrolysis resistance, which comprises the following steps:

[0008] (1) providing a substrate and growing a buffer layer on one side thereof;

[0009] (2) growing a u-GaN layer on the buffer layer;

[0010] (3) The doping concentration of the u-GaN layer is 5×10 18 ~10×10 18 cm -3 a first n-GaN layer;

[0011] (4) growing an n-AlGaN layer with a thickness of 10 to 100 nm on the first N-GaN layer;

[0012] (5) The doping concentration of the n-AlGaN layer is 1×10 18 ~3×10 19 cm-3 a second n-GaN layer;

[0013] (6) growing a plurality of periodic InGaN / GaN layers on the second n-GaN layer;

[0014] (7) growing a quantum well layer on the InGaN / GaN layer;

[0015] (8) The doping concentration of the quantum well layer is 5×10 19 ~1.5×10 20 cm -3 a first p-GaN layer;

[0016] (9) growing a p-AlGaN layer on the first p-GaN layer;

[0017] (10) The p-AlGaN layer is grown with a doping concentration of 1×10 18 ~1×10 20 cm -3 The second p-GaN layer is formed to obtain a blue-green LED epitaxial wafer with high hydrolysis resistance.

[0018] As an improvement of the above technical solution, in step (2), the growth rate of the u-GaN layer is 5 to 8 μm / h, and the growth temperature is 900 to 1200° C.;

[0019] The thickness of the u-GaN layer is 1-3 μm.

[0020] As an improvement to the above technical solution, in step (3), the doping concentration of the first n-GaN layer is 7.5×10 18 ~8.5×10 18 cm -3 , its growth rate is 3-6 μm / h, and the growth temperature is 1050-1100°C;

[0021] The thickness of the first n-GaN layer is 0.5-2 μm.

[0022] As an improvement to the above technical solution, in step (5), the doping concentration of the second n-GaN layer is 1×10 19 ~3×10 19 cm -3 , its growth rate is 3-5 μm / h, and the growth temperature is 950-1050℃;

[0023] The thickness of the second n-GaN layer is 1.5-2 μm.

[0024] As an improvement of the above technical solution, in step (4), the thickness of the n-AlGaN layer is 30 to 60 nm, and the growth temperature is 950 to 1050°C.

[0025] As an improvement of the above technical solution, step (1) includes:

[0026] (1.1) Providing a substrate, and subjecting the substrate to a high temperature treatment at 1000-1200° C. in a hydrogen atmosphere for 5-20 minutes;

[0027] (1.2) Grow a GaN layer with a thickness of 10 to 100 nm on the substrate obtained in step (1.1) at a growth temperature of 500 to 900°C.

[0028] As an improvement of the above technical solution, in step (6), the thickness of the InGaN layer in each period is 0.5-10 nm, the thickness of the GaN layer is 10-100 nm, and the growth temperature is 600-1000° C.;

[0029] In step (7), the quantum well layer includes a plurality of In x Ga 1-x N well layer and multiple GaN barrier layers; wherein each In x Ga 1-x The thickness of the N well layer is 1-6 nm, and the growth temperature is 600-900° C.; the thickness of each GaN barrier layer is 1-20 nm, and the growth temperature is 700-1000° C.

[0030] As an improvement of the above technical solution, in step (8), the growth temperature of the first p-GaN layer is 700-800°C;

[0031] In step (9), the thickness of the p-AlGaN layer is 10-100 nm, the growth temperature is 700-1000° C., and the Mg doping concentration is 1×10 18 ~2×10 20 cm -3 , the Al doping concentration is 1×10 19 ~1×10 21 cm -3 ;

[0032] In step (10), the thickness of the second p-GaN layer is 10-100 nm, and the growth temperature thereof is 700-1000°C.

[0033] Correspondingly, the present invention also discloses a blue-green LED epitaxial wafer structure with high hydrolysis resistance, which is prepared by the above method.

[0034] Correspondingly, the present invention also discloses a blue-green LED epitaxial wafer with high hydrolysis resistance, which includes the above-mentioned epitaxial structure.

[0035] The implementation of the present invention has the following beneficial effects:

[0036] The present invention relates to a method for preparing a blue-green LED epitaxial wafer structure with high hydrolysis resistance. An n-AlGaN layer is grown between the first n-GaN layer and the second n-GaN layer, which can effectively block defects. Furthermore, by controlling the growth rates of the u-GaN layer, the first n-GaN layer, and the second n-GaN layer, the quality of the crystals grown before and after can be made consistent, without the presence of a metamorphic layer. This improves the quality and density of the epitaxial crystals and enhances hydrolysis resistance. Using the epitaxial wafer prepared using the above-mentioned preparation method, the LED chip does not require an ISO deep etching process or a chip sidewall protection process, and the LED chip can be used for a long time under high temperature and high humidity conditions. BRIEF DESCRIPTION OF THE DRAWINGS

[0037] Figure 1 This is a flow chart of a method for preparing a blue-green LED epitaxial wafer structure with high hydrolysis resistance in one embodiment of the present invention;

[0038] Figure 2 This is an electron microscope image of the LED chip obtained by preparing the epitaxial structure in Example 2-4 of the present invention after 288 hours of high temperature and high humidity etching;

[0039] Figure 3 This is an electron microscope image of the LED chip in Comparative Example 2 of the present invention after 288 hours of high temperature and high humidity corrosion;

[0040] Figure 4 This is a graph showing the corrosion of the LED chip obtained by the epitaxial structure in Example 2-4 of the present invention after 288 hours of high temperature and high humidity corrosion;

[0041] Figure 5 This is a corrosion microscope image of the LED chip in Comparative Example 2 of the present invention after 288 hours of high temperature and high humidity corrosion;

[0042] Figure 6 This is a corrosion microscope image of the LED chip in Comparative Example 2 of the present invention after 288 hours of high temperature and high humidity corrosion. DETAILED DESCRIPTION

[0043] In order to make the objectives, technical solutions and advantages of the present invention more clear, the present invention is described in further detail below.

[0044] The present invention provides a method for preparing a blue-green LED epitaxial wafer structure with high hydrolysis resistance, which comprises the following steps:

[0045] S1: providing a substrate and growing a buffer layer on one side thereof;

[0046] Specifically, S1 includes:

[0047] S101: providing a substrate, and subjecting the substrate to high temperature treatment at 1000-1200° C. in a hydrogen atmosphere for 5-20 minutes;

[0048] Specifically, the substrate may be silicon carbide and / or sapphire, but is not limited thereto; sapphire is preferred. Surface impurities may be removed by hydrogen treatment.

[0049] S102: growing a GaN layer on the substrate obtained in step S11;

[0050] Specifically, the growth temperature of the GaN layer is 500-900° C., and the thickness thereof is 10-100 nm; its main function is to serve as a low-temperature buffer layer.

[0051] S2: growing a u-GaN layer on the buffer layer;

[0052] Specifically, the u-GaN layer is grown at a rate of 5 to 8 μm / h and a temperature of 900 to 1200°C. The u-GaN grown under these conditions has high crystal quality and high density. Specifically, after growth, the u-GaN layer is 1 to 3 μm thick.

[0053] S3: growing a first n-GaN layer on the u-GaN layer;

[0054] Specifically, the growth rate of the first n-GaN layer is 3-6 μm / h, and the growth temperature is 1050-1100° C.; preferably, the growth temperature is 1060-1085° C.

[0055] After the growth is completed, the thickness of the first n-GaN layer is 0.5 to 2 μm, and the Si doping concentration is 5×10 18 ~10×10 18 cm -3 , preferably 7.5×10 18 ~8.5×10 18 cm -3 , more preferably 8×10 18 cm -3 .

[0056] S4: growing an n-AlGaN layer on the first n-GaN layer;

[0057] Specifically, the growth temperature of the n-AlGaN layer is 950-1050°C.

[0058] After growth is complete, the thickness of the n-AlGaN layer is 10 to 100 nm, preferably 30 to 60 nm. The n-AlGaN layer effectively blocks defects in the u-GaN layer and the first n-GaN layer from extending into the second n-GaN layer, improving crystal growth quality and reducing the likelihood of epitaxial metamorphic layers.

[0059] S5: growing a second n-GaN layer on the n-AlGaN layer;

[0060] Specifically, the growth rate of the second n-GaN layer is 3-5 μm / h, and the growth temperature is 950-1050° C.; preferably, the growth temperature is 950-1000° C.

[0061] After the growth is completed, the thickness of the second n-GaN layer is 1.5 to 2 μm, and the Si doping concentration is 1×10 18 ~3×10 19 cm -3 , preferably 1×10 19 ~3×10 19 cm -3 .

[0062] S6: growing a plurality of InGaN / GaN layers on the second n-GaN layer;

[0063] Specifically, the thickness of the InGaN layer in each period is 0.5-10 nm, the thickness of the GaN layer is 10-100 nm, and the growth temperature thereof is 600-1000° C. The InGaN / GaN layer is a stress release layer.

[0064] S7: growing a quantum well layer on the InGaN / GaN layer;

[0065] Specifically, the quantum well layer includes multiple In x Ga 1-x N well layer and multiple GaN barrier layers; wherein each In x Ga 1-x The thickness of the N well layer is 1-6 nm, and the growth temperature is 600-900° C.; the thickness of each GaN barrier layer is 1-20 nm, and the growth temperature is 700-1000° C.

[0066] S8: growing a first p-GaN layer on the quantum well layer;

[0067] Specifically, the Mg doping concentration in the first p-GaN layer is 5×10 19 ~1.5×10 20 cm -3 , its growth temperature is 700~800℃.

[0068] S9: growing a p-AlGaN layer on the first p-GaN layer;

[0069] Specifically, the thickness of the p-AlGaN layer is 10-100 nm, the growth temperature is 700-1000° C., and the Mg doping concentration is 1×10 18 ~2×10 20 cm-3 , the Al doping concentration is 1×10 19 ~1×10 21 cm -3 .

[0070] S10: growing a second p-GaN layer on the p-AlGaN layer, thereby obtaining a blue-green LED epitaxial wafer with high hydrolysis resistance;

[0071] Specifically, the thickness of the second p-GaN layer is 10-100 nm, the growth temperature is 700-1000° C., and the Mg doping concentration is 1×10 18 ~1×10 20 cm -3 .

[0072] Preferably, the method for preparing an epitaxial structure for LED with high hydrolysis resistance in the present invention further comprises the following steps:

[0073] S11: growing a contact layer on the second p-GaN layer, annealing for 10 to 30 minutes, and cooling.

[0074] The growth temperature of the contact layer is 750-950°C, and the Mg doping concentration is 1×10 19 ~1×10 21 cm -3 After the growth is completed, the thickness of the contact layer is 1 to 5 nm.

[0075] Correspondingly, the present invention also discloses a blue-green LED epitaxial wafer structure with high hydrolysis resistance, which is prepared by the above-mentioned preparation method.

[0076] Accordingly, the present invention also discloses a blue-green LED with high hydrolysis resistance, which can be a face-mounted LED, a flip-chip LED, or a vertical LED, but is not limited thereto. When the epitaxial structure of the present invention is used, the LED does not require an ISO deep etching process or chip sidewall protection process.

[0077] The present invention will be described below with specific embodiments:

[0078] Example Group 1

[0079] This embodiment group provides a method for preparing a blue-green LED epitaxial wafer structure with high hydrolysis resistance, which includes the following steps:

[0080] 1. High-temperature treatment of a sapphire composite substrate (a 20 nm thick AlN layer was deposited on a sapphire patterned substrate by PECVD magnetron sputtering) at 1050°C for 3 minutes in a hydrogen atmosphere with a reaction chamber pressure maintained at 500 Torr.

[0081] 2. Cool down to 830°C, maintain the reaction chamber pressure at 500 Torr, and grow a 10nm thick low-temperature buffer layer of GaN on the sapphire composite substrate;

[0082] 3. Raise the temperature to 1050°C, maintain the reaction chamber pressure at 300 Torr, and continue growing a 1.2μm u-GaN layer at a growth rate of 4.5μm / h.

[0083] 4. Then, the first n-GaN layer is grown at a temperature of 1080°C and a pressure of 200 torr, with a Si doping concentration of A1, a thickness of 0.5 μm, and a growth rate of 8 μm / h.

[0084] 5. Cool down to 1000℃ and grow n-AlGaN layer with thickness of δ.

[0085] 6. Grow a second n-GaN layer at 1000°C with Si doping concentration A2, a thickness of 1.5 μm, and a growth rate of 2.5 μm / h;

[0086] 7. Cool down to 870°C, maintain the pressure of the reaction chamber at 200 torr, and grow the InGaN / GaN superlattice stress release layer.

[0087] 8. Cool down to 750°C, periodically grow the active layer MQW, and maintain the pressure of the reaction chamber at 200 Torr.

[0088] 9. Continue to grow the first p-GaN layer at a low temperature of 750°C and a pressure of 200 torr, with a Mg doping concentration of 1×10 20 cm -3 .

[0089] 10. Raise the temperature to 950°C, maintain the pressure in the reaction chamber at 100 torr, and continue to grow a 30nm p-AlGaN layer with an Al doping concentration of 2×10 20 cm -3 .

[0090] 11. Raise the temperature to 950℃, maintain the pressure of the reaction chamber at 200torr, and continue to grow the second p-GaN layer of 40nm, with a Mg doping concentration of 5×10 19 cm -3 ;

[0091] 12. Finally, cool to 850°C, grow a 3nm thick contact layer, anneal for 20 minutes, and then cool in the furnace.

[0092] The specific parameters of each embodiment are shown in the following table, and the performance test thereof is shown in the following table:

[0093]

[0094]

[0095] Comparative Example Group 1

[0096] This comparative example group provides a method for preparing a blue-green LED epitaxial wafer structure with high hydrolysis resistance. The main differences between this method and Example Group 1 are as follows:

[0097]

[0098] It can be seen from Examples 1-1 to 1-5 that the epitaxial structure prepared by the preparation method of the present invention has a maximum hydrolysis resistance time of ≥290h, indicating that it has good hydrolysis resistance under high temperature and high humidity conditions.

[0099] Comparison of Examples 1-5 with Comparative Examples 1-1 to 1-6 shows that the first n-GaN layer, n-AlGaN layer, and second n-GaN layer of the present invention work together well to improve hydrolysis resistance. Without one of these layers, or by varying their thickness or doping concentration, the technical effects of the present invention cannot be achieved.

[0100] Comparative Example 2

[0101] This comparative example provides a hydrolysis-resistant LED chip, which is prepared using the method of 201911334175.5 (without the epitaxial structure of the present invention and with the provision of an isolation groove). After testing, its maximum hydrolysis resistance is 280 hours.

[0102] Example Group 2

[0103] This embodiment group provides a method for preparing a blue-green LED epitaxial wafer structure with high hydrolysis resistance, which includes the following steps:

[0104] 1. High-temperature treatment of a sapphire composite substrate (a 20 nm thick AlN layer was deposited on a sapphire patterned substrate by PECVD magnetron sputtering) at 1050°C for 3 minutes in a hydrogen atmosphere with a reaction chamber pressure maintained at 500 Torr.

[0105] 2. Cool down to 600°C, maintain the reaction chamber pressure at 400 torr, and grow a 10nm thick low-temperature buffer layer of GaN on the sapphire composite substrate;

[0106] 3. Raise the temperature to 1100°C, maintain the reaction chamber pressure at 250 Torr, and continue growing a 1.2μm u-GaN layer at a growth rate of v1.

[0107] 4. Then the first n-GaN layer is grown at a temperature of 1080°C and a pressure of 200 torr, with a Si doping concentration of 8×10 18 cm -3 , thickness is 1.5 μm, growth rate is v2;

[0108] 5. Cool down to 980℃ and grow n-AlGaN layer with a thickness of 50nm.

[0109] 6. Grow the second n-GaN layer at 1000°C with Si doping concentration of 1.5×10 19 cm -3 , thickness is 2 μm, growth rate is v3;

[0110] 7. Cool down to 800°C, maintain the pressure of the reaction chamber at 200 torr, and grow the InGaN / GaN superlattice stress release layer.

[0111] 8. Cool down to 700℃, periodically grow the active layer MQW, and maintain the pressure of the reaction chamber at 200 torr.

[0112] 9. Maintain 700℃ and pressure 200torr to grow the first p-GaN layer with Mg doping concentration of 1.2×10 20 cm -3 .

[0113] 10. Raise the temperature to 950°C, maintain the pressure in the reaction chamber at 100 torr, and continue to grow a 30nm p-AlGaN layer with an Al doping concentration of 3×10 20 cm -3 .

[0114] 11. Raise the temperature to 950℃, maintain the pressure of the reaction chamber at 200torr, and continue to grow the second p-GaN layer of 40nm, with a Mg doping concentration of 5×10 19 cm -3 ;

[0115] 12. Finally, cool to 850°C, grow a 3nm thick contact layer, anneal for 20 minutes, and then cool in the furnace.

[0116] The specific parameters of each embodiment are shown in the following table, and the performance test thereof is shown in the following table:

[0117]

[0118] It can be seen from Examples 2-1 to 2-5 that the growth rates of the u-GaN layer, the first n-GaN layer, and the second n-GaN layer in the preparation method of the present invention have a great influence on the hydrolysis resistance.

[0119] Test example

[0120] The specific testing methods for the epitaxial structures in Example Group 1, Comparative Example Group 1, Comparative Example 2, and Example Group 2 are as follows:

[0121] (1) Maximum anti-hydrolysis time

[0122] The epitaxial structures obtained in each embodiment and comparative example were prepared into upright LED chips according to traditional methods (reference document 201810417428.4), and then measured using existing equipment (CN202010143107.7). Specifically, the test temperature was 85°C and the humidity was 90% RH; the chips were taken out every 5 hours and observed under a high-power microscope. If there was corrosion, the previous time was taken as the maximum anti-hydrolysis time; if there was no corrosion, the chips were placed in the equipment and the test continued.

[0123] (2) Characterization of hydrolysis resistance

[0124] The LED chips prepared from the epitaxial structures of Comparative Example 2 and Examples 2-4 were tested using existing equipment (CN202010143107.7). Specifically, the test temperature was 85°C and the humidity was 90% RH. The LED chips were taken out after 288 hours of continuous testing. The surface conditions were observed. The results are as follows: Figures 2 to 6 As shown, from Figure 2 、 Figure 4 It can be seen that after high temperature and high humidity treatment, there is no degenerate layer in the epitaxial structure of the present invention, and the surface of the LED chip is not corroded. Figure 3 、 Figure 5 、 Figure 6 It can be seen that after high temperature and high humidity treatment, the LED chips produced by existing technology have obvious deterioration layers in the epitaxial structure. The surface also has abnormal electrode PV circles, abnormal electrode positions, and corrosion on the n-PAD side cutting streets.

[0125] The above is a preferred embodiment of the invention. It should be pointed out that for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the principles of the invention. These improvements and modifications are also considered to be within the scope of protection of the present invention.

Claims

1. A method for preparing a blue-green LED epitaxial wafer structure with high hydrolysis resistance, characterized in that: The following steps are involved: (1) Providing a substrate and growing a buffer layer on one side thereof; (2) growing a u-GaN layer on the buffer layer; the u-GaN layer has a growth rate of 5 to 8 μm / h and a thickness of 1 to 3 μm; (3) The doping concentration of the u-GaN layer is 7.5×10 18 ~8.5×10 18 cm -3 The first n-GaN layer has a growth rate of 3 to 6 μm / h and a thickness of 0.5 to 2 μm. (4) growing an n-AlGaN layer with a thickness of 10 to 100 nm on the first n-GaN layer; (5) The doping concentration of the n-AlGaN layer is 1×10 19 ~3×10 19 cm -3 The second n-GaN layer has a growth rate of 3~5μm / h and a thickness of 1.5~2μm; (6) growing a plurality of periodic InGaN / GaN layers on the second n-GaN layer; (7) growing a quantum well layer on the InGaN / GaN layer; (8) The doping concentration of the quantum well layer is 5×10 19 ~1.5×10 20 cm -3 a first p-GaN layer; (9) growing a p-AlGaN layer on the first p-GaN layer; (10) The p-AlGaN layer is grown with a doping concentration of 1×10 18 ~1×10 20 cm -3 The second p-GaN layer is formed to obtain a blue-green LED epitaxial wafer with high hydrolysis resistance.

2. The method for preparing a blue-green LED epitaxial wafer structure with high hydrolysis resistance according to claim 1, wherein: In step (2), the growth temperature of the u-GaN layer is 900~1200℃.

3. The method for preparing a blue-green LED epitaxial wafer structure with high hydrolysis resistance according to claim 1, wherein: In step (3), the growth temperature of the first n-GaN layer is 1050~1100℃.

4. The method for preparing a blue-green LED epitaxial wafer structure with high hydrolysis resistance according to claim 1, wherein: In step (5), the growth temperature of the second n-GaN layer is 950~1050℃.

5. The method for preparing a blue-green LED epitaxial wafer structure with high hydrolysis resistance according to claim 1, wherein: In step (4), the thickness of the n-AlGaN layer is 30-60 nm, and the growth temperature is 950-1050° C.

6. The method for preparing a blue-green LED epitaxial wafer structure with high hydrolysis resistance according to claim 1, wherein: Step (1) includes: (1.1) Providing a substrate, and subjecting the substrate to a high temperature treatment at 1000-1200°C in a hydrogen atmosphere for 5-20 minutes; (1.2) Grow a GaN layer with a thickness of 10 to 100 nm on the substrate obtained in step (1.1) at a growth temperature of 500 to 900°C.

7. The method for preparing a blue-green LED epitaxial wafer structure with high hydrolysis resistance according to claim 1, wherein: In step (6), the thickness of the InGaN layer in each period is 0.5-10 nm, the thickness of the GaN layer is 10-100 nm, and the growth temperature is 600-1000°C; In step (7), the quantum well layer includes multiple In x Ga 1-x N well layer and multiple GaN barrier layers; wherein each In x Ga 1-x The thickness of the N-well layer is 1~6nm, and the growth temperature is 600~900℃; the thickness of each GaN barrier layer is 1~20nm, and the growth temperature is 700~1000℃.

8. The method for preparing a blue-green LED epitaxial wafer structure with high hydrolysis resistance according to claim 1, wherein: In step (8), the growth temperature of the first p-GaN layer is 700-800°C; In step (9), the thickness of the p-AlGaN layer is 10-100 nm, the growth temperature is 700-1000°C, and the Mg doping concentration is 1×10 18 ~2×10 20 cm -3 , the Al doping concentration is 1×10 19 ~1×10 21 cm -3 ; In step (10), the thickness of the second p-GaN layer is 10-100 nm, and the growth temperature thereof is 700-1000° C.

9. A blue-green LED epitaxial wafer with high hydrolysis resistance, characterized in that: It is prepared by the preparation method according to any one of claims 1 to 8.

10. A blue-green LED with high hydrolysis resistance, characterized in that: It comprises the blue-green LED epitaxial wafer with high hydrolysis resistance as claimed in claim 9.

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