Light emitting diode and method of fabrication

Abstract

This application provides a light-emitting diode (LED) and its fabrication method. The LED includes a stress-relieving layer and a quantum well layer protection structure. The quantum well layer protection structure includes at least one sequentially deposited cyclic structure. Each cyclic structure includes: an AlGaN barrier layer, a first AlN protective layer, a second AlN protective layer, a first AlInN protective layer, an InGaN well layer, a second AlInN protective layer, a third AlN protective layer, and a fourth AlN protective layer sequentially deposited on the stress-relieving layer. The In content in both the first and second AlInN protective layers gradually increases from away from the InGaN well layer to closer to the InGaN well layer. By setting the first and second AlInN protective layers, a high In content is ensured in the InGaN well layer, thereby obtaining a high-quality, high-efficiency red-yellow light InGaN well layer and ensuring the luminous efficiency of the LED.

Description

Technical Field

[0001] This application relates to the field of semiconductor technology, and in particular to a light-emitting diode and its fabrication method. Background Technology

[0002] A light-emitting diode (LED) is a commonly used light-emitting device that releases light through the recombination of electrons and holes. It has wide applications in the lighting field. LEDs efficiently convert electrical energy into light energy and have extensive uses in modern society, such as lighting, flat panel displays, and medical devices. This electronic component first appeared in 1962, initially emitting only low-intensity red light. Later, versions emitting other monochromatic lights were developed, and the light emitted now encompasses visible light, infrared, and ultraviolet light, with significantly increased luminous intensity. Its applications have expanded from initial use as indicator lights and display panels; with continuous technological advancements, LEDs are now widely used in displays and lighting.

[0003] In commercial applications, AlInGaP (aluminum indium gallium phosphide) is commonly used for developing red LED structures. However, as chip size continues to shrink, the efficiency of AlInGaP-based red LEDs drops sharply. In contrast, InGaN (indium gallium nitride), due to its smaller carrier diffusion coefficient, lower surface recombination rate, and extremely strong carrier localization, exhibits higher luminous efficiency and a lower efficiency drop than AlInGaP in smaller sizes.

[0004] However, the indium (In) content in InGaN is unstable and easily precipitates out. As the In content decreases, the luminous efficiency of the light-emitting diode decreases. Summary of the Invention

[0005] This application provides a light-emitting diode and its fabrication method to solve the problem of low luminous efficiency caused by the analysis of the In group in light-emitting diodes.

[0006] The first aspect of this application provides a light-emitting diode, including a stress-relieving layer;

[0007] A quantum well layer protective structure deposited on the stress relief layer;

[0008] The quantum well layer protection structure includes at least one sequentially deposited cyclic structure, each of the cyclic structures comprising:

[0009] An AlGaN barrier layer, a first AlN protective layer, a second AlN protective layer, a first AlInN protective layer, and an InGaN well layer are sequentially deposited on the stress relief layer, wherein the In content in the first AlInN protective layer gradually increases from the direction away from the InGaN well layer to the direction closer to the InGaN well layer.

[0010] A second AlInN protective layer, a third AlN protective layer, and a fourth AlN protective layer are sequentially deposited on the InGaN well layer, wherein the In content in the second AlInN protective layer gradually increases from the direction away from the InGaN well layer to the direction closer to the InGaN well layer.

[0011] In one possible implementation, the loop structure has a loop count greater than or equal to 3.

[0012] In one feasible manner, the deposition temperature of the first AlInN protective layer is 700–800°C, and the deposition thickness is 1–20 Å.

[0013] The Al component content in the first AlInN protective layer gradually decreases from the direction away from the InGaN well layer to the direction closer to the InGaN well layer.

[0014] In one feasible manner, the deposition temperature of the second AlInN protective layer is 700–800°C, and the deposition thickness is 1–20 Å.

[0015] The Al component content in the second AlInN protective layer gradually decreases from the direction away from the InGaN well layer to the direction closer to the InGaN well layer.

[0016] In one feasible manner, the InGaN well layer is deposited at a temperature of 700–800°C and the deposition thickness is 10–50 Å.

[0017] The In content of the InGaN well layer is 10% to 50%.

[0018] In one feasible approach, the deposition temperature of the first AlN protective layer is 800–900°C, and the deposition thickness is 1–20 Å.

[0019] The deposition temperature of the second AlN protective layer is 700–800℃, and the deposition thickness is 1–20 Å.

[0020] In one feasible manner, the deposition temperature of the third AlN protective layer is 700–800°C, and the deposition thickness is 1–20 Å.

[0021] The deposition temperature of the fourth AlN protective layer is 800–900℃, and the deposition thickness is 1–20 Å.

[0022] In one feasible manner, the deposition temperature of the second AlN protective layer is lower than the deposition temperature of the first AlN protective layer;

[0023] The deposition temperature of the third AlN protective layer is lower than that of the first AlN protective layer.

[0024] In one feasible embodiment, the AlGaN barrier layer is Si-doped AlGaN with a doping concentration of 1E17–1E18 atoms / cm³. 3 The deposition temperature is 800–900℃, and the deposition thickness is 30–200 Å.

[0025] A second aspect of this application provides a method for fabricating a light-emitting diode, comprising:

[0026] Deposition stress relief layer;

[0027] A quantum well layer protective structure is deposited on the stress relief layer;

[0028] The quantum well layer protection structure includes at least one sequentially deposited cyclic structure, each of the cyclic structures comprising:

[0029] An AlGaN barrier layer, a first AlN protective layer, a second AlN protective layer, a first AlInN protective layer, and an InGaN well layer are sequentially deposited on the stress relief layer, wherein the In content in the first AlInN protective layer gradually increases from the direction away from the InGaN well layer to the direction closer to the InGaN well layer;

[0030] A second AlInN protective layer, a third AlN protective layer, and a fourth AlN protective layer are sequentially deposited on the InGaN well layer, wherein the In content in the second AlInN protective layer gradually increases from the direction away from the InGaN well layer to the direction closer to the InGaN well layer.

[0031] This application provides a light-emitting diode (LED) and its fabrication method. The LED includes at least one sequentially deposited cyclic structure. Each cyclic structure includes: an AlGaN barrier layer, a first AlN protective layer, a second AlN protective layer, a first AlInN protective layer, and an InGaN well layer sequentially deposited on a stress relief layer. The In content in the first AlInN protective layer gradually increases from away from the InGaN well layer to near the InGaN well layer. A second AlInN protective layer, a third AlN protective layer, and a fourth AlN protective layer are sequentially deposited on the InGaN well layer. The In content in the second AlInN protective layer gradually increases from away from the InGaN well layer to near the InGaN well layer. By setting the first and second AlInN protective layers to protect the InGaN well layer, a high In content is ensured in the InGaN well layer, resulting in a high-quality, high-efficiency red-yellow light InGaN well layer, thereby ensuring the luminous efficiency of the LED. Attached Figure Description

[0032] To more clearly illustrate the technical solution of this application, the drawings used in the embodiments will be briefly introduced below. Obviously, for those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0033] Figure 1 This is a schematic diagram of the structure of a light-emitting diode provided in an embodiment of this application;

[0034] Figure 2 This is a schematic diagram of the fabrication method of a light-emitting diode provided in an embodiment of this application.

[0035] Figure label:

[0036] 1-Stress relief layer; 2-AlGaN barrier layer; 3-First AlN protective layer; 4-Second AlN protective layer; 5-First AlInN protective layer; 6-InGaN well layer; 7-Second AlInN protective layer; 8-Third AlN protective layer; 9-Fourth AlN protective layer; 10-Substrate; 11-Buffer layer; 12-Unintentionally doped layer; 13-Electron donor layer; 14-Electron blocking layer; 15-Hole donor layer; 16-Ohmic contact layer. Detailed Implementation

[0037] The embodiments will now be described in detail, examples of which are illustrated in the accompanying drawings. When the following description relates to the drawings, unless otherwise indicated, the same numbers in different drawings represent the same or similar elements. The embodiments described below do not represent all embodiments consistent with this application. They are merely examples of systems and methods consistent with some aspects of this application as detailed in the claims.

[0038] To facilitate understanding of the technical solution of this application, some concepts involved in the embodiments of this application will be explained first below:

[0039] Deposition refers to the process by which substances transported by a moving medium settle and accumulate in a suitable location due to changes in conditions.

[0040] A potential barrier, also known as a potential barrier, is a barrier layer formed by the diffusion of electrons and holes in a PN (negative, positive, and negative) junction. The potential energy difference between the two sides is called the potential barrier.

[0041] The active layer of a typical semiconductor laser is about 0.1-0.3 μm thick. When the thickness of the active layer is reduced to the order of Bohr radius or de Broglie wavelength, the quantum size effect occurs. At this time, the charge carriers are confined in the potential well formed by the active layer, which is called a quantum well.

[0042] During the fabrication of light-emitting diodes (LEDs), the In component in the InGaN light-emitting layer is unstable and easily precipitates. As the In component precipitates in the InGaN light-emitting layer, the In component content in the InGaN light-emitting layer gradually decreases, resulting in a decrease in the luminous efficiency of the LED.

[0043] For the reasons mentioned above, this application proposes a light-emitting diode and its fabrication method. Protective layers are formed on both sides of the InGaN well layer to protect it, thereby suppressing the precipitation of In components in the InGaN well layer and effectively ensuring the luminous efficiency of the light-emitting diode.

[0044] Figure 1 This is a schematic diagram of the structure of a light-emitting diode provided in an embodiment of this application.

[0045] See Figure 1 The light-emitting diode provided in this application embodiment includes a stress relief layer 1 and a quantum well layer protective structure deposited on the stress relief layer 1.

[0046] The quantum well layer protection structure includes at least one cyclic structure deposited sequentially. Each cyclic structure includes: an aluminum gallium nitride (AlGaN) barrier layer 2, a first aluminum nitride (AlN) protective layer 3, a second AlN protective layer 4, a first aluminum indium nitride (AlInN) protective layer 5, and an indium gallium nitride (InGaN) well layer 6 deposited on a stress relief layer 1. The indium (In) content in the first AlInN protective layer 5 gradually increases from away from the InGaN well layer 6 to closer to the InGaN well layer 6.

[0047] A second AlInN protective layer 7, a third AlN protective layer 8, and a fourth AlN protective layer 9 are sequentially deposited on the InGaN well layer 6. The In content of the second AlInN protective layer 7 gradually increases from the direction away from the InGaN well layer 6 to the direction closer to the InGaN well layer 6.

[0048] Specifically, an AlGaN barrier layer 2, a first AlN protective layer 3, a second AlN protective layer 4, a first AlInN protective layer 5, an InGaN well layer 6, a second AlInN protective layer 7, a third AlN protective layer 8, and a fourth AlN protective layer 9 are sequentially deposited on the stress relief layer 1, so that the upper and lower surfaces of the InGaN well layer 6 are covered by the first AlInN protective layer 5 and the second AlInN protective layer 7.

[0049] Furthermore, the In content in both the first AlInN protective layer 5 and the second AlInN protective layer 7 gradually increases from the direction away from the InGaN well layer 6 to the direction closer to the InGaN well layer 6, in order to ensure the In content of the InGaN well layer 6, avoid the precipitation of In components, and ensure that the InGaN well layer 6 contains a high In content, so as to obtain a high-quality, high-luminous-efficiency red and yellow light InGaN well layer 6, thereby ensuring the luminous efficiency of the light-emitting diode.

[0050] The first AlN protective layer 3, the second AlN protective layer 4, the third AlN protective layer 8, and the fourth AlN protective layer 9 wrap around the first AlInN protective layer 5 and the second AlInN protective layer 7, thus protecting the first AlInN protective layer 5 and the second AlInN protective layer 7 and forming a closed-loop quantum well layer protection structure.

[0051] In the specific implementation, the number of iterations of the loop structure is greater than or equal to 3.

[0052] For example, if the number of cycles in the cyclic structure is 3, a cyclic structure consisting of three AlGaN barrier layers 2, first AlN protective layer 3, second AlN protective layer 4, first AlInN protective layer 5, InGaN well layer 6, second AlInN protective layer 7, third AlN protective layer 8 and fourth AlN protective layer 9 can be deposited sequentially on the stress relief layer 1.

[0053] If the number of cycles is 5, a cyclic structure consisting of five layers can be deposited sequentially on the stress relief layer 1: AlGaN barrier layer 2, first AlN protective layer 3, second AlN protective layer 4, first AlInN protective layer 5, InGaN well layer 6, second AlInN protective layer 7, third AlN protective layer 8, and fourth AlN protective layer 9. This process can be repeated, and the number of cycles can be adjusted according to actual conditions. This embodiment does not limit the number of cycles.

[0054] The deposition temperature of the first AlInN protective layer 5 can be 700-800℃, and the deposition thickness can be 1-20 Å. The Al content in the first AlInN protective layer 5 gradually decreases from the direction away from the InGaN well layer 6 to the direction closer to the InGaN well layer 6.

[0055] Specifically, the temperature for depositing the first AlInN protective layer 5 can be between 700 and 800°C.

[0056] For example, the temperature used to deposit the first AlInN protective layer 5 can be 700°C, 710°C, 720°C, 730°C, 740°C, 750°C, 760°C, 770°C, 780°C, 790°C or 800°C, or other temperature values ​​not shown between 700°C and 800°C.

[0057] Preferably, the temperature used for depositing the first AlInN protective layer 5 is between 720 and 780°C. The specific temperature value can be adjusted accordingly at different stages of the actual work, but it should not be understood that a single temperature must be maintained from the beginning to the end of depositing the first AlInN protective layer 5. Instead, the temperature can be adjusted within a reasonable range, such as between 720 and 770°C or between 780 and 800°C.

[0058] The thickness of the first AlInN protective layer 5 is between 1 and 20 Å.

[0059] For example, the deposition thickness of the first AlInN protective layer 5 can be 2A, 4A, 6A, 8A, 10A, 12A, 14A, 16A or 20A, or other deposition thicknesses not shown in 1 to 20A.

[0060] Preferably, the deposition thickness of the first AlInN protective layer 5 can be 1 to 10 Å.

[0061] The Al content in the first AlInN protective layer 5 gradually decreases from the direction away from the InGaN well layer 6 to the direction closer to the InGaN well layer 6. At the same time, the In content in the first AlInN protective layer 5 gradually increases from the direction away from the InGaN well layer 6 to the direction closer to the InGaN well layer 6.

[0062] In practice, when depositing the first AlInN protective layer 5, the inflow of In source and Al source can be controlled by a flow controller, so that the In component content gradually increases and the Al component content gradually decreases from the direction away from the InGaN well layer 6 to the direction closer to the InGaN well layer 6, thereby suppressing the precipitation of In component in the InGaN well layer 6 and effectively ensuring the luminous efficiency of the light-emitting diode.

[0063] The deposition temperature of the second AlInN protective layer 7 is 700–800℃, and the deposition thickness is 1–20 Å. The Al content in the second AlInN protective layer 7 gradually decreases from the direction away from the InGaN well layer 6 to the direction closer to the InGaN well layer 6.

[0064] Specifically, the temperature for depositing the second AlInN protective layer 7 is between 700 and 800°C.

[0065] For example, the temperature used to deposit the second AlInN protective layer 7 can be 700°C, 710°C, 720°C, 730°C, 740°C, 750°C, 760°C, 770°C, 780°C, 790°C or 800°C, or other temperature values ​​not shown between 700°C and 800°C.

[0066] Preferably, the temperature used for depositing the second AlInN protective layer 7 is between 720 and 780°C. The specific temperature value can be adjusted accordingly at different stages of the actual work, but it should not be understood that a certain temperature must be maintained from the beginning to the end of depositing the second AlInN protective layer 7. Instead, the temperature can be adjusted within a reasonable temperature range, such as between 720 and 770°C or between 780 and 800°C.

[0067] The deposition thickness of the second AlInN protective layer 7 is between 1 and 20 Å.

[0068] For example, the deposition thickness of the second AlInN protective layer 7 can be 2A, 4A, 6A, 8A, 10A, 12A, 14A, 16A or 20A, or other deposition thicknesses not shown in 1 to 20A.

[0069] Preferably, the deposition thickness of the second AlInN protective layer 7 can be 1 to 10 Å.

[0070] The Al content in the second AlInN protective layer 7 gradually decreases from the direction away from the InGaN well layer 6 to the direction closer to the InGaN well layer 6. At the same time, the In content in the second AlInN protective layer 7 gradually increases from the direction away from the InGaN well layer 6 to the direction closer to the InGaN well layer 6.

[0071] In practice, when depositing the second AlInN protective layer 7, the inflow of In source and Al source can be controlled by a flow controller, so that the In component content gradually increases and the Al component content gradually decreases from the direction away from the InGaN well layer 6 to the direction closer to the InGaN well layer 6, thereby suppressing the precipitation of In component in the InGaN well layer 6 and effectively ensuring the luminous efficiency of the light-emitting diode.

[0072] Specifically, by setting a first AlInN protective layer 5 and a second AlInN protective layer 7 to wrap the InGaN well layer 6, the precipitation of In components in the InGaN well layer 6 is effectively avoided, thus ensuring the luminous efficiency of the light-emitting diode.

[0073] In practice, the deposition temperature of the InGaN well layer 6 can be between 700 and 800°C.

[0074] For example, the temperature used to deposit the InGaN well layer 6 can be 700°C, 710°C, 720°C, 730°C, 740°C, 750°C, 760°C, 770°C, 780°C, 790°C or 800°C, or other temperature values ​​not shown between 700°C and 800°C.

[0075] Preferably, the temperature used for depositing the InGaN well layer 6 can be between 720 and 780°C. The specific temperature value can be adjusted accordingly at different stages of the actual operation. It should not be understood that a certain temperature must be maintained from the beginning to the end of depositing the InGaN well layer 6. Instead, the temperature can be adjusted within a reasonable temperature range, such as between 720 and 770°C or between 780 and 800°C.

[0076] The deposition thickness of the InGaN well layer 6 can be between 10 and 50 Å.

[0077] For example, the deposition thickness of the InGaN well layer 6 can be 10 Å, 15 Å, 20 Å, 25 Å, 30 Å, 35 Å, 40 Å, 45 Å or 50 Å, or other deposition thicknesses not shown in the range of 10 to 50 Å.

[0078] Preferably, the deposition thickness of the InGaN well layer 6 can be between 20 and 40 Å.

[0079] The In composition content of InGaN well layer 6 is 10-50%.

[0080] For example, the In component content of the InGaN well layer 6 can be 10%, 15%, 20%, 25%, 30%, 35%, 40%, 45%, or 50%, or other In component contents not shown in the range of 10% to 50%.

[0081] In practice, the deposition temperature of the first AlN protective layer 3 can be 800–900℃.

[0082] For example, the temperature used to deposit the first AlN protective layer 3 can be 800°C, 810°C, 820°C, 830°C, 840°C, 850°C, 860°C, 870°C, 880°C, 890°C or 900°C, or other temperature values ​​not shown between 800°C and 900°C.

[0083] Preferably, the temperature used for depositing the first AlN protective layer 3 can be between 820 and 880°C. The specific temperature value can be adjusted accordingly at different stages of the actual work, but it should not be understood that a certain temperature must be maintained from the beginning to the end of depositing the first AlN protective layer 3. Instead, the temperature can be adjusted within a reasonable temperature range, such as between 820 and 870°C or between 880 and 900°C.

[0084] The deposition thickness of the first AlN protective layer 3 can be between 1 and 20 Å.

[0085] For example, the deposition thickness of the first AlN protective layer 3 can be 2A, 4A, 6A, 8A, 10A, 12A, 14A, 16A or 20A, or other deposition thicknesses not shown in 1 to 20A.

[0086] Preferably, the deposition thickness of the first AlN protective layer 3 can be between 1 and 10 Å.

[0087] In practice, the deposition temperature of the second AlN protective layer 4 can be 700–800℃.

[0088] For example, the temperature used to deposit the second AlN protective layer 4 can be 700°C, 710°C, 720°C, 730°C, 740°C, 750°C, 760°C, 770°C, 780°C, 790°C or 800°C, or other temperature values ​​not shown between 700°C and 800°C.

[0089] Preferably, the temperature used for depositing the second AlN protective layer 4 can be between 720 and 780°C. The specific temperature value can be adjusted accordingly at different stages of the actual work, but it should not be understood that a certain temperature must be maintained from the beginning to the end of depositing the second AlN protective layer 4. Instead, the temperature can be adjusted within a reasonable temperature range, such as between 720 and 770°C or between 780 and 800°C.

[0090] The deposition thickness of the second AlN protective layer 4 can be between 1 and 20 Å.

[0091] For example, the deposition thickness of the second AlN protective layer 4 can be 2A, 4A, 6A, 8A, 10A, 12A, 14A, 16A or 20A, or other deposition thicknesses not shown in 1 to 20A.

[0092] Preferably, the deposition thickness of the second AlN protective layer 4 can be between 1 and 10 Å.

[0093] The deposition temperature of the second AlN protective layer 4 is lower than that of the first AlN protective layer 3. Thus, the second AlN protective layer 4 acts as a low-temperature protective layer for the first AlN protective layer 3, while the first AlN protective layer 3 acts as a high-temperature protective layer for the second AlN protective layer 4. It is worth noting that the first AlN protective layer 3 is located away from the InGaN well layer 6, while the second AlN protective layer 4 is located close to the InGaN well layer 6. Since the InGaN well layer 6 requires a lower deposition temperature, the deposition of the second AlN protective layer 4 is set at a lower temperature than that of the first AlN protective layer 3, thus protecting the InGaN well layer 6 without causing damage.

[0094] In practice, the deposition temperature of the third AlN protective layer 8 can be 700–800℃.

[0095] For example, the temperature used to deposit the third AlN protective layer 8 can be 700°C, 710°C, 720°C, 730°C, 740°C, 750°C, 760°C, 770°C, 780°C, 790°C or 800°C, or other temperature values ​​not shown between 700°C and 800°C.

[0096] Preferably, the temperature used for depositing the third AlN protective layer 8 can be between 720 and 780°C. The specific temperature value can be adjusted accordingly at different stages of the actual work, but it should not be understood that a certain temperature must be maintained from the beginning to the end of depositing the third AlN protective layer 8. Instead, the temperature can be adjusted within a reasonable temperature range, such as between 720 and 770°C or between 780 and 800°C.

[0097] The deposition thickness of the third AlN protective layer 8 can be between 1 and 20 Å.

[0098] For example, the deposition thickness of the third AlN protective layer 8 can be 2A, 4A, 6A, 8A, 10A, 12A, 14A, 16A or 20A, or other deposition thicknesses not shown in 1 to 20A.

[0099] Preferably, the deposition thickness of the third AlN protective layer 8 can be between 1 and 10 Å.

[0100] In practice, the deposition temperature of the fourth AlN protective layer 9 can be 800–900℃.

[0101] For example, the temperature used to deposit the fourth AlN protective layer 9 can be 800°C, 810°C, 820°C, 830°C, 840°C, 850°C, 860°C, 870°C, 880°C, 890°C or 900°C, or other temperature values ​​not shown between 800°C and 900°C.

[0102] Preferably, the temperature used for depositing the fourth AlN protective layer 9 can be between 820 and 880°C. The specific temperature value can be adjusted accordingly at different stages of the actual operation, but it should not be understood that a certain temperature must be maintained from the beginning to the end of depositing the InGaN well layer 6. Instead, the temperature can be adjusted within a reasonable temperature range, such as between 820 and 870°C or between 880 and 900°C.

[0103] The thickness of the fourth AlN protective layer 9 is between 1 and 20 Å.

[0104] For example, the deposition thickness of the fourth AlN protective layer 9 can be 2A, 4A, 6A, 8A, 10A, 12A, 14A, 16A or 20A, or other deposition thicknesses not shown in 1 to 20A.

[0105] Preferably, the deposition thickness of the fourth AlN protective layer 9 can be between 1 and 10 Å.

[0106] The deposition temperature of the third AlN protective layer 8 is lower than that of the first AlN protective layer 3. Thus, the third AlN protective layer 8 acts as a low-temperature protective layer for the first AlN protective layer 3, and the first AlN protective layer 3 acts as a high-temperature protective layer for the third AlN protective layer 8. It is worth noting that the first AlN protective layer 3 is far from the InGaN well layer 6, while the third AlN protective layer 8 is close to the InGaN well layer 6. Since the InGaN well layer 6 requires a lower deposition temperature, the protective layer is designed to prevent high-temperature damage to it. Therefore, by setting the deposition temperature of the third AlN protective layer 8 to be lower than that of the first AlN protective layer 3, it protects the InGaN well layer 6 without causing damage to it.

[0107] Similarly, the deposition temperature of the third AlN protective layer 8 is lower than that of the fourth AlN protective layer 9. Thus, for the fourth AlN protective layer 9, the third AlN protective layer 8 is a low-temperature protective layer; and for the third AlN protective layer 8, the fourth AlN protective layer 9 is a high-temperature protective layer. It is worth noting that the fourth AlN protective layer 9 is far from the InGaN well layer 6, while the third AlN protective layer 8 is close to the InGaN well layer 6. The InGaN well layer 6 requires a lower deposition temperature. When setting a protective layer on it, to avoid high-temperature damage to the InGaN well layer 6, the deposition temperature of the third AlN protective layer 8 is set lower than that of the fourth AlN protective layer 9, thus protecting the InGaN well layer 6 without causing damage to it.

[0108] In the specific implementation, AlGaN barrier layer 2 is silicon-doped AlGaN, with a doping concentration of 1E17 to 1E18 atoms per cubic centimeter. 3 .

[0109] The deposition temperature of the AlGaN barrier layer 2 can be 800–900℃.

[0110] For example, the temperature used to deposit the AlGa barrier layer can be 800°C, 810°C, 820°C, 830°C, 840°C, 850°C, 860°C, 870°C, 880°C, 890°C, or 900°C, or other temperature values ​​not shown between 800°C and 900°C.

[0111] Preferably, the temperature used for depositing the AlGaN barrier layer 2 can be between 820 and 880°C. The specific temperature value can be adjusted accordingly at different stages of the actual work, but it should not be understood that a single temperature must be maintained from the beginning to the end of depositing the AlGaN barrier layer 2. Instead, the temperature can be adjusted within a reasonable range, such as between 820 and 870°C or between 880 and 900°C.

[0112] Specifically, in order to effectively suppress the precipitation of In components, a higher temperature can be used to deposit the InGaN well layer 6 and the AlGaN barrier layer 2. Since the deposition temperature of the InGaN well layer 6 should not be too high, the deposition temperature of the AlGaN barrier layer 2 is set to be higher than that of the InGaN well layer 6, thereby forming a high-quality, high-luminescence base red and yellow light InGaN well layer 6.

[0113] The deposition thickness of the AlGaN barrier layer 2 can be 30–200 Å.

[0114] For example, the deposition thickness of the AlGaN barrier layer 2 can be 40 Å, 60 Å, 80 Å, 100 Å, 120 Å, 140 Å, 160 Å, 180 Å or 200 Å, or other deposition thicknesses not shown in the range of 30 to 200 Å.

[0115] Preferably, the deposition thickness of the AlGaN barrier layer 2 can be 80–150 Å.

[0116] In a specific implementation, the light-emitting diode also includes a substrate 10 and a buffer layer 11, an unintentionally doped layer 12, and an electron-providing layer 13 sequentially deposited on the substrate 10. A stress-relieving layer 1 is deposited on the electron-providing layer 13.

[0117] An electron-blocking layer 14 (EBL), a hole-providing layer 15, and an ohmic contact layer 16 are also deposited on top of the quantum well layer protective structure.

[0118] Figure 2 This is a schematic flowchart of a method for fabricating a light-emitting diode (LED) according to an embodiment of this application.

[0119] See Figure 2 The method for preparing the light-emitting diode provided in this application is implemented by the following steps S100-S200.

[0120] Step S100: Deposit a stress-relieving layer;

[0121] Specifically, the light-emitting diode provided in this application embodiment includes a substrate and a buffer layer, an unintentionally doped layer, and an electron-providing layer sequentially deposited on the substrate. A stress-relieving layer is deposited on the electron-providing layer.

[0122] Step S200: Deposit a quantum well layer protective structure on the stress relief layer.

[0123] Specifically, the quantum well layer protection structure includes at least one cyclic structure deposited sequentially. Each cyclic structure includes: sequentially depositing an AlGaN barrier layer, a first AlN protection layer, a second AlN protection layer, a first AlInN protection layer, and an InGaN well layer on a stress relief layer, wherein the In content in the first AlInN protection layer gradually increases from the direction away from the InGaN well layer to the direction closer to the InGaN well layer; and sequentially depositing a second AlInN protection layer, a third AlN protection layer, and a fourth AlN protection layer on the InGaN well layer, wherein the In content in the second AlInN protection layer gradually increases from the direction away from the InGaN well layer to the direction closer to the InGaN well layer.

[0124] In this case, the number of iterations in the loop structure is greater than or equal to 3.

[0125] The deposition temperature of the first AlInN protective layer is 700–800℃, and the deposition thickness is 1–20 Å. The Al content in the first AlInN protective layer gradually decreases from the direction away from the InGaN well layer to the direction closer to the InGaN well layer.

[0126] The deposition temperature of the second AlInN protective layer is 700–800℃, and the deposition thickness is 1–20 Å.

[0127] The Al content in the second AlInN protective layer gradually decreases from the direction away from the InGaN well layer to the direction closer to the InGaN well layer.

[0128] The deposition temperature of the InGaN well layer is 700–800℃, and the deposition thickness is 10–50 Å; the In content of the InGaN well layer is 10–50%.

[0129] The deposition temperature of the first AlN protective layer is 800–900℃, and the deposition thickness is 1–20 Å; the deposition temperature of the second AlN protective layer is 700–800℃, and the deposition thickness is 1–20 Å; the deposition temperature of the third AlN protective layer is 700–800℃, and the deposition thickness is 1–20 Å; the deposition temperature of the fourth AlN protective layer is 800–900℃, and the deposition thickness is 1–20 Å.

[0130] The deposition temperature of the second AlN protective layer is lower than that of the first AlN protective layer.

[0131] The deposition temperature of the third AlN protective layer is lower than that of the first AlN protective layer.

[0132] The AlGaN barrier is made of Si-doped AlGaN with a doping concentration of 1E17–1E18 atoms / cm³. 3 The deposition temperature is 800–900℃, and the deposition thickness is 30–200 Å.

[0133] Specifically, by setting a first AlInN protective layer and a second AlInN protective layer to protect the InGaN well layer, a high In component content is ensured in the InGaN well layer, so as to obtain a high-quality, high-efficiency red and yellow light InGaN well layer, thereby ensuring the luminous efficiency of the light-emitting diode.

[0134] Similar parts between the embodiments provided in this application can be referred to mutually. The specific implementation methods provided above are only a few examples under the overall concept of this application and do not constitute a limitation on the scope of protection of this application. For those skilled in the art, any other implementation methods extended from the solution of this application without creative effort shall fall within the scope of protection of this application.

Claims

1. A light-emitting diode, characterized in that, include Stress relief layer; A quantum well layer protective structure deposited on the stress relief layer; The quantum well layer protection structure includes at least one sequentially deposited cyclic structure, each of the cyclic structures comprising: An AlGaN barrier layer, a first AlN protective layer, a second AlN protective layer, a first AlInN protective layer, and an InGaN well layer are sequentially deposited on the stress relief layer, wherein the In content in the first AlInN protective layer gradually increases from the direction away from the InGaN well layer to the direction closer to the InGaN well layer. A second AlInN protective layer, a third AlN protective layer, and a fourth AlN protective layer are sequentially deposited on the InGaN well layer, wherein the In content in the second AlInN protective layer gradually increases from the direction away from the InGaN well layer to the direction closer to the InGaN well layer; The deposition temperature of the first AlInN protective layer is 700–800℃, and the deposition thickness is 1–20 Å. The Al component content in the first AlInN protective layer gradually decreases from the direction away from the InGaN well layer to the direction closer to the InGaN well layer; The deposition temperature of the second AlInN protective layer is 700–800℃, and the deposition thickness is 1–20 Å. The Al component content in the second AlInN protective layer gradually decreases from the direction away from the InGaN well layer to the direction closer to the InGaN well layer.

2. The light-emitting diode according to claim 1, characterized in that, The number of iterations in the loop structure is greater than or equal to 3.

3. The light-emitting diode according to claim 1, characterized in that, The deposition temperature of the InGaN well layer is 700–800℃, and the deposition thickness is 10–50 Å. The In composition of the InGaN well layer is 10-50%.

4. The light-emitting diode according to claim 1, characterized in that, The deposition temperature of the first AlN protective layer is 800–900℃, and the deposition thickness is 1–20 Å. The deposition temperature of the second AlN protective layer is 700–800℃, and the deposition thickness is 1–20 Å.

5. The light-emitting diode according to claim 4, characterized in that, The deposition temperature of the third AlN protective layer is 700–800℃, and the deposition thickness is 1–20 Å. The deposition temperature of the fourth AlN protective layer is 800–900℃, and the deposition thickness is 1–20 Å.

6. The light-emitting diode according to claim 5, characterized in that, The deposition temperature of the second AlN protective layer is lower than that of the first AlN protective layer; The deposition temperature of the third AlN protective layer is lower than that of the first AlN protective layer.

7. The light-emitting diode according to claim 1, characterized in that, The AlGaN barrier layer is Si-doped AlGaN with a doping concentration of 1E17 to 1E18 atoms / cm3, a deposition temperature of 800 to 900℃, and a deposition thickness of 30 to 200 Å.

8. A method for fabricating a light-emitting diode, characterized in that, include: Deposition stress relief layer; A quantum well layer protective structure is deposited on the stress relief layer; The quantum well layer protection structure includes at least one sequentially deposited cyclic structure, each of the cyclic structures comprising: An AlGaN barrier layer, a first AlN protective layer, a second AlN protective layer, a first AlInN protective layer, and an InGaN well layer are sequentially deposited on the stress relief layer, wherein the In content in the first AlInN protective layer gradually increases from the direction away from the InGaN well layer to the direction closer to the InGaN well layer; A second AlInN protective layer, a third AlN protective layer, and a fourth AlN protective layer are sequentially deposited on the InGaN well layer, wherein the In content in the second AlInN protective layer gradually increases from the direction away from the InGaN well layer to the direction closer to the InGaN well layer; The deposition temperature of the first AlInN protective layer is 700–800℃, and the deposition thickness is 1–20 Å. The Al component content in the first AlInN protective layer gradually decreases from the direction away from the InGaN well layer to the direction closer to the InGaN well layer; The deposition temperature of the second AlInN protective layer is 700–800°C, and the deposition thickness is 1–20 Å. The Al content in the second AlInN protective layer gradually decreases from the direction away from the InGaN well layer to the direction closer to the InGaN well layer.

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