A red micro light emitting diode epitaxial wafer and a preparation method thereof

Abstract

The application discloses a high-light-efficiency structural red light Micro LED epitaxial wafer manufacturing method and belongs to the field of light-emitting diode semiconductors. The method comprises a substrate and P-type GaAs buffer layers, P-type GaInP etching stop layers, P-type GaAs ohmic contact layers, P-type GaInP electrode firm layers, P-type AlGaInP current expansion layers, P-type AlInP restriction layers, P-type AlGaInP waveguide layers, P-type electron blocking layers, quantum well layers, N-type AlGaInP waveguide layers, N-type AlInP restriction layers, N-type AlGaInP transition layers, N-type GaP superlattice expansion layers and N-type GaP ohmic contact layers which are sequentially grown on the substrate. The growth mode of N-type and P-type doping is inverted, and the N-type GaP adopts an epitaxial structure of a superlattice expansion layer, i.e. a composite layer of a periodically stacked high-temperature GaP / low-temperature GaP, instead of a conventional Micro epitaxial structure. The photoelectric performance of the Micro red light product is improved by adjusting and optimizing the epitaxial structure, and the problem of high-light-efficiency red light Micro light-emitting diodes at home and abroad is effectively solved.

Description

Technical Field

[0001] This invention relates to the field of light-emitting diode semiconductors, specifically to a red micro light-emitting diode epitaxial wafer and its fabrication method. Background Technology

[0002] Micro LED's technological advantages lie in its high brightness, wide color gamut, and high reliability. It is also easy to achieve flexibility, transparency, free splicing, and sensor integration. Furthermore, its wide applicability across various fields, from micro-displays to consumer electronics and large-screen displays, has led to its widespread recognition as the next-generation display technology. Micro LED's high resolution, fast response, low energy consumption, and long lifespan give it enormous potential in ultra-small and ultra-large displays, such as virtual reality (VR), augmented reality (AR), smartwatches, and electronic billboards. Beyond traditional display applications, Micro LED also shows broad application prospects in fields such as biosensors, optogenetics, and visible light communication.

[0003] Although Micro LED technology is in a phase of rapid development, its enormous potential in the display field makes it an important direction for the future development of display technology, but it still faces many challenges. As an emerging display technology, Micro LED has made significant progress in research and application in recent years, but it also faces some technical challenges.

[0004] like Figure 1 This is a conventional epitaxial structure for red Micro LEDs. Currently, there are two main issues:

[0005] Carrier injection imbalance: Due to the much higher electron mobility (~500 cm² / V·s) than hole mobility (~50 cm² / V·s), high-energy electrons injected into the active region of a multiple quantum well (MQW) can easily overcome the potential barrier of the quantum wells under strong electric fields or thermal excitation. Electrons directly pass through the active region and are injected into the P-type region, where they are captured by the non-radiative recombination centers, resulting in optical power loss and poor stability of the product's high and low temperature performance.

[0006] Chip manufacturing processes are complex: such as Figure 3 This diagram illustrates the process technology for a conventional micro-epitaxial chip. The standard chip manufacturing process requires transferring the epitaxial layer grown on a GaAs substrate onto a transparent sapphire substrate. This is followed by bonding the epitaxial layer to a temporary substrate, removing the original GaAs substrate, and then performing a second bonding transfer to the final display backplane. This process requires at least two substrate transfers. This procedure is costly, has high yield challenges, and is prone to introducing damage.

[0007] Therefore, improving the luminous efficiency and yield of Micro LEDs has become a technical challenge in the industry. Summary of the Invention

[0008] To address the aforementioned problems, this invention provides a method for manufacturing a high-efficiency structural red-light-emitting Micro LED epitaxial wafer. The LED comprises a substrate and, sequentially grown on the substrate, a P-type GaAs buffer layer, a P-type GaInP etching stop layer, a P-type GaAs ohmic contact layer, a P-type GaInP electrode bonding layer, a P-type AlGaInP current spreading layer, a P-type AlInP confinement layer, a P-type AlGaInP waveguide layer, a P-type electron blocking layer, a quantum well layer, an N-type AlGaInP waveguide layer, an N-type AlInP confinement layer, an N-type AlGaInP transition layer, an N-type GaP superlattice extension layer, and an N-type GaP ohmic contact layer. By employing an inverted growth method of N-type and P-type doping, and using an epitaxial structure of a superlattice extension layer (i.e., a periodic high-temperature GaP / low-temperature GaP stacked composite layer) for the N-type GaP, the invention replaces the conventional Micro epitaxial structure, thereby improving the problems existing in current Micro products.

[0009] This invention is achieved through the following technical solution:

[0010] An epitaxial wafer for a red-light micro-emitting diode includes a GaAs substrate 600 and, sequentially grown on the GaAs substrate 600, a P-type GaAs buffer layer 601, a P-type GaInP etching stop layer 200, a P-type GaAs ohmic contact layer 201, a P-type GaInP electrode bonding layer 202, a P-type AlGaInP current spreading layer 203, a P-type AlInP confinement layer 204, a P-type AlGaInP waveguide layer 205, a multiple quantum well layer 206, an N-type AlGaInP waveguide layer 207, an N-type AlInP confinement layer 208, an N-type AlGaInP transition layer 209, an N-type GaP superlattice spreading layer 210, and an N-type GaP ohmic contact layer 211.

[0011] Preferably, the N-type GaP superlattice current extension layer 210 is formed by periodically alternating stacks of high-temperature grown GaP sublayers and low-temperature grown GaP sublayers to achieve anisotropy of electrical properties, namely low-resistance transport in the vertical direction and efficient extension in the horizontal direction.

[0012] Preferably, the multi-quantum-well layer comprises an AlGaInP quantum barrier and an AlGaInP quantum well.

[0013] A method for fabricating a red-light-emitting micro-LED epitaxial wafer includes the following steps: growing a P-type GaAs buffer layer on a GaAs substrate; growing a P-type GaInP etch-off layer on the P-type GaAs buffer layer; growing a P-type GaAs ohmic contact layer on the P-type GaInP etch-off layer; growing a P-type GaInP electrode bonding layer on the P-type GaAs ohmic contact layer; growing a P-type AlGaInP current spreading layer on the P-type GaInP electrode bonding layer; growing a P-type AlInP confinement layer on the P-type AlGaInP current spreading layer; and growing a P-type AlGaInP waveguide layer on the P-type AlInP confinement layer. A P-type AlGaInP waveguide layer is grown on the P-type AlGaInP waveguide layer. A multi-quantum well layer is grown on the P-type AlGaInP waveguide layer. An N-type AlGaInP waveguide layer is grown on the multi-quantum well layer. An N-type AlInP confinement layer is grown on the N-type AlGaInP waveguide layer. An N-type AlGaInP transition layer is grown on the N-type AlGaInP confinement layer. An N-type GaP superlattice current spreading layer is grown on the N-type AlGaInP transition layer. An N-type GaP ohmic contact layer is grown on the N-type GaP superlattice current spreading layer.

[0014] Preferably, the specific steps include: growing a p-type GaAs buffer layer 601 with a thickness of 1500~3000 Å on a GaAs substrate 600; introducing a p-type doping source, wherein the doping source is Cp2Mg or diethylzinc, and the doping concentration is 1×10⁻⁶. 18 ~3×10 18 carriers / cm 3 ;

[0015] A p-type GaInP etching stop layer of 200 nm with a thickness of 1000–2000 Å is grown. A p-type doping source, either Cp₂Mg or diethylzinc, is introduced, with a doping concentration of 1 × 10⁻⁶. 18 ~3×10 18 carriers / cm 3 ;

[0016] A p-type GaAs ohmic contact layer 201 with a thickness of 500~800 Å is grown and a p-type doping source is introduced. The doping source is Cp2Mg or diethylzinc, and the doping concentration is >5×10⁻⁶. 18 carriers / cm 3 ;

[0017] A p-type GaInP electrode bonding layer 202 with a thickness of 100~500 Å is grown, and a p-type doping source is introduced. The doping source is Cp2Mg or diethylzinc, and the doping concentration is 1× 10⁻⁶. 18 ~3×10 18 carriers / cm3 ;

[0018] A p-type AlGaInP current-extended layer 203 was grown with a thickness of 5000–15000 Å. The Al composition was designed to be between 0.7 and 1. A p-type doping source was introduced, with the doping source being either Cp₂Mg or diethylzinc, and the doping concentration being 1.5 × 10⁻⁶. 18 ~3×10 18 carriers / cm 3 ;

[0019] A p-type AlInP confinement layer 204 with a thickness of 2000–4000 Å was grown and p-type doping was introduced. The doping source was Cp₂Mg or diethylzinc, and the doping concentration was 1 × 10⁻⁶. 18 ~2×10 18 carriers / cm 3 ;

[0020] A P-type AlGaInP waveguide layer 205 was grown with a thickness of 500~1500 Å and an Al composition designed to be between 0.6 and 0.9. This layer was undoped.

[0021] A multi-quantum well layer 206 is grown, wherein the quantum well material is AlGaInP with a thickness of 30~50 Å, the quantum well barrier material is AlGaInP with a thickness of 50~100 Å, the Al composition of the barrier is designed to be 0.6~1, and the number of pairs of potential wells and barriers is 3~8. This layer is undoped.

[0022] N-type AlGaInP waveguide layer 207 was grown with a thickness of 500~1500 Å and an Al composition designed to be between 0.6 and 0.9. This layer was undoped.

[0023] An N-type AlInP confinement layer 208 with a thickness of 2000–3000 Å was grown, and an N-type doping source was introduced. The doping source was either Si₂H₆ or SiH₄, and the doping concentration was 1 × 10⁻⁶. 18 ~2×10 18 carriers / cm 3 ;

[0024] An N-type AlGaInP transition layer 209 with a thickness of 200–400 Å was grown, and an N-type doping source was introduced. The doping source was either Si₂H₆ or SiH₄, and the doping concentration was 4 × 10⁻⁶. 18 ~6×10 18 carriers / cm 3 ;

[0025] A current-extended N-type GaP superlattice layer 210 is grown. This layer is a periodic composite layer of GaP grown at alternating high and low temperatures: HT-GaP layers (780–810 °C, 600–1000 Å thickness) and LT-GaP layers (730–760 °C, 150–250 Å thickness). The temperature difference between the HT-GaP and LT-GaP layers is greater than 50 °C. The number of superlattice composite layers is 20–60 pairs. An N-type doping source (Si₂H₆ or SiH₄) is introduced, with an HT-GaP doping concentration of 3 × 10⁻⁶. 18 ~4×10 18 carriers / cm 3 LT-GaP doping concentration 1× 10 18 ~2×10 18 carriers / cm 3 ;

[0026] An N-type GaP ohmic contact layer 211 with a thickness of 300~800 Å is grown and an N-type doping source is introduced. The doping source is Si2H6 or SiH4, and the doping concentration is >5×10⁻⁶. 19 carriers / cm 3 .

[0027] Compared with the prior art, the beneficial effects of the present invention are:

[0028] 1. Superior current spread: The epitaxial wafer structure of this invention adopts an N-type GaP superlattice extension layer, which combines high longitudinal conductivity with excellent lateral spread capability, thus solving the current congestion problem of Micro LED.

[0029] 2. Balanced carrier injection: The epitaxial wafer structure of this invention adopts a rebalancing design of "one decrease and one increase" in mobility to make the injection of electrons and holes more matched, thereby improving the carrier recombination efficiency and uniformity in the quantum well and improving the luminous efficiency and temperature characteristics of the device.

[0030] 3. Simplified manufacturing process: The epitaxial wafer of this invention adopts a PN inverted structure, realizing a chip fabrication process that requires only one substrate transfer, which significantly reduces the complexity and cost of the Micro LED mass transfer process.

[0031] 4. Improved device reliability: The epitaxial structure of this invention has a more uniform current distribution and balanced carrier injection, which helps to reduce local hot spots, thereby extending device lifetime.

[0032] This invention improves the photoelectric performance of Micro red light products by adjusting and optimizing the epitaxial structure, effectively solving the current domestic and international problems in high-efficiency red light-emitting diodes and realizing industrialization. It is of great strategic significance for enhancing the company's core competitiveness, brand value and corporate image. Attached Figure Description

[0033] Figure 1 It is the epitaxial structure of a conventional red Micro LED;

[0034] Figure 2 This is a schematic diagram of the epitaxial wafer structure of the present invention;

[0035] Figure 3 This is a process diagram for the fabrication of a conventional micro epitaxial structure chip.

[0036] Figure 4 This is a schematic diagram of a chip structure fabricated using the epitaxial structure of the present invention.

[0037] In the figure: 600, GaAs substrate; 601, P-type GaAs buffer layer; 200, P-type GaInP etch stop layer; 201, P-type GaAs ohmic contact layer; 202, P-type GaInP electrode bonding layer; 203, P-type AlGaInP current spreading layer; 204, P-type AlInP confinement layer; 205, P-type AlGaInP waveguide layer; 206, multiple quantum well layer; 207, N-type AlGaInP waveguide layer; 208, N-type AlInP confinement layer; 209, N-type AlGaInP transition layer; 210, N-type GaP superlattice spreading layer; 211, N-type GaP ohmic contact layer. Detailed Implementation

[0038] The present invention will be further described below with reference to the accompanying drawings:

[0039] Example

[0040] As attached Figure 3As shown, a red-light-emitting micro-LED epitaxial wafer includes a GaAs substrate 600 and, sequentially grown on the GaAs substrate 600, a P-type GaAs buffer layer 601, a P-type GaInP etch stop layer 200, a P-type GaAs ohmic contact layer 201, a P-type GaInP electrode bonding layer 202, a P-type AlGaInP current spreading layer 203, a P-type AlInP confinement layer 204, a P-type AlGaInP waveguide layer 205, a multiple quantum well layer 206, an N-type AlGaInP waveguide layer 207, an N-type AlInP confinement layer 208, an N-type AlGaInP transition layer 209, an N-type GaP superlattice spreading layer 210, and an N-type GaP ohmic contact layer 211. The N-type GaP superlattice current spreading layer 210 is formed by periodically alternating stacks of high-temperature grown GaP sublayers and low-temperature grown GaP sublayers to achieve anisotropy of electrical performance with low-resistance transport in the vertical direction and efficient spreading in the horizontal direction.

[0041] A method for fabricating a red-light-emitting micro-LED epitaxial wafer includes the following steps: First, a P-type GaAs buffer layer 601 with a thickness of 2500 Å is grown on a GaAs substrate 600. Then, a P-type doping source is introduced, the doping source being Cp₂Mg with a doping concentration of 2 × 10⁻⁶. 18 carriers / cm 3 ;

[0042] A 1500 Å thick P-type GaInP etching stop layer was grown at a depth of 200 Å. A P-type doping source, Cp₂Mg, with a doping concentration of 2.5 × 10⁻⁶ Å, was introduced. 18 carriers / cm 3 ;

[0043] A p-type GaAs ohmic contact layer 201 with a thickness of 700 Å was grown and a p-type doped source, Cp₂Mg, was introduced with a doping concentration of 6.0 × 10⁻⁶. 18 carriers / cm 3 ;

[0044] A 300 Å thick P-type GaInP electrode robust layer 202 was grown and introduced, with a P-type doping source of Cp₂Mg and a doping concentration of 2 × 10⁻⁶. 18 carriers / cm 3 ;

[0045] A p-type AlGaInP current-extended layer 203 with a thickness of 10000 Å and an Al composition of 0.8 was grown. A p-type doped source, Cp₂Mg, was introduced with a doping concentration of 2 × 10⁻⁶. 18 carriers / cm 3 ;

[0046] A p-type AlInP confinement layer 204 with a thickness of 3000 Å was grown and p-type doping was introduced. The doping source was Cp₂Mg, and the doping concentration was 1.5 × 10⁻⁶. 18 carriers / cm 3 ;

[0047] A P-type AlGaInP waveguide layer 205 with a thickness of 1000 Å and an Al composition of 0.8 was grown and left undoped.

[0048] A multi-quantum well layer 206 is grown, wherein the quantum well material is AlGaInP with a thickness of 40 Å, the quantum well barrier material is AlGaInP with a thickness of 80 Å, the Al composition of the barrier is 0.7, and the number of pairs of potential wells and barriers is 7. This layer is undoped.

[0049] An N-type AlGaInP waveguide layer 207 with a thickness of 1000 Å and an Al composition of 0.8 was grown and left undoped.

[0050] An N-type AlInP confinement layer 208 with a thickness of 2500 Å was grown and an N-type doping source, Si2H6, was introduced with a doping concentration of 2 × 10⁻⁶. 18 carriers / cm 3 ;

[0051] An N-type AlGaInP transition layer 209 with a thickness of 300 Å was grown and an N-type doping source, Si2H6, was introduced with a doping concentration of 5 × 10⁻⁶. 18 carriers / cm 3 ;

[0052] A current-extended N-type GaP superlattice layer 210 was grown. This layer is a periodic composite layer of GaP grown at alternating high and low temperatures: HT-GaP and LT-GaP. The HT-GaP layer is grown at a high temperature of 800℃, with a thickness of 800 Å per layer. The LT-GaP layer is grown at a low temperature of 740℃, with a thickness of 200 Å per layer. The temperature difference between the HT-GaP and LT-GaP layers is greater than 50℃. The number of superlattice composite layers is 50 pairs. An N-type doping source, Si₂H₆, is introduced, with an HT-GaP doping concentration of 4 × 10⁻⁶. 18 carriers / cm 3 LT-GaP doping concentration 2×10 18 carriers / cm 3 ;

[0053] An N-type GaP ohmic contact layer 211 with a thickness of 700 Å was grown and introduced with an N-type doped source, Si2H6, with a doping concentration of 6 × 10⁻⁶. 19 carriers / cm 3 .

[0054] 1. This invention innovatively proposes an N-type GaP superlattice current-extending layer:

[0055] This invention does not grow a single N-type GaP layer, but rather employs an alternating high-temperature and low-temperature growth method to form an N-type GaP superlattice extended layer. Specifically, this superlattice is composed of two sublayers grown alternately and periodically: At higher temperatures, the carbon content of the material is significantly reduced, resulting in a layer with high-concentration Si doping. This layer has high crystal quality, low resistivity, and is primarily responsible for efficient electron transport in the vertical direction. At lower temperatures, the material has a high carbon content, resulting in a layer co-doped with Si and C. The introduction of C atoms can adjust the stress and band structure of the material, and this layer optimizes the lateral conductivity, promoting excellent electron expansion in the horizontal direction. Through this alternating design of "high-temperature high-doping – vertical transport" and "low-temperature co-doping – lateral expansion," this invention creates a superlattice extended layer with anisotropically optimized conductivity, achieving a current expansion effect far exceeding that of a uniform monolayer GaP.

[0056] 2. Overall mobility balance:

[0057] In conventional structures, N-type AlGaInP exhibits extremely high electron mobility, while P-type AlInP / AlGaInP has very low hole mobility, resulting in a severe imbalance. In this invention, N-type GaP, with its relatively lower electron mobility, is chosen to actively reduce the injection rate at the electron end, allowing for better matching with the hole end, thereby improving overall performance and temperature stability. Although the electron mobility of N-type GaP is lower than that of N-type AlGaInP in conventional structures, it acts as a buffer, ensuring a more balanced rate of electron and hole injection into the quantum well active region. This balanced carrier injection promotes a more concentrated recombination region at the center of the active region, reducing overflow and significantly improving the device's efficiency stability and temperature characteristics under high current.

[0058] 3. Simplification of manufacturing process:

[0059] Because the structure of this invention is an inverted structure with P on the bottom and N on top, after epitaxial growth is completed on the GaAs substrate, N-type ohmic electrodes can first be fabricated on the top N-type GaP superlattice layer and bonded to the final display driver backplane. Subsequently, the native GaAs substrate can be directly removed, and etching can be performed down to the P-type GaAs layer to fabricate P-type electrodes. Figure 4As shown, this process requires only one substrate transfer, omitting the temporary substrate transfer step necessary in conventional methods, which greatly simplifies the process, reduces costs, and improves production yield.

[0060] The following table compares the epitaxial wafer structure of this invention with that of a conventional epitaxial structure:

[0061]

[0062] The experimental data also show that the internal quantum efficiency of the optimized structure is 7% higher than that of the conventional structure. Therefore, the structure of this invention can prevent the problem of electrons rapidly transitioning to the P-type region and the sidewalls of the chip, thereby improving the luminous efficacy of red Micro LEDs under low current.

[0063] The above description is merely a specific embodiment of this application, but the scope of protection of this application is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the technical scope disclosed in this application should be included within the scope of protection of this application. Therefore, the scope of protection of this application should be determined by the scope of the claims.

Claims

1. A red micro light-emitting diode epitaxial wafer, characterized in that: The epitaxial wafer adopts an N-type and P-type doped inverted structure, including a GaAs substrate and sequentially grown on the GaAs substrate a P-type GaAs buffer layer, a P-type GaInP etch stop layer, a P-type GaAs ohmic contact layer, a P-type GaInP electrode bonding layer, a P-type AlGaInP current spreading layer, a P-type AlInP confinement layer, a P-type AlGaInP waveguide layer, a multiple quantum well layer, an N-type AlGaInP waveguide layer, an N-type AlInP confinement layer, an N-type AlGaInP transition layer, an N-type GaP superlattice spreading layer, and an N-type GaP ohmic contact layer.

2. The red micro light-emitting diode epitaxial wafer according to claim 1, characterized in that: The N-type GaP superlattice current extension layer is formed by periodically stacking high-temperature grown GaP sublayers and low-temperature grown GaP sublayers to achieve anisotropy of electrical properties, namely low-resistance transport in the vertical direction and efficient extension in the horizontal direction.

3. The red micro light-emitting diode epitaxial wafer according to claim 1, characterized in that: The multi-quantum-well layer includes AlGaInP quantum barriers and AlGaInP quantum wells.

4. A method for fabricating a red-light-emitting micro-LED epitaxial wafer, characterized in that: The process includes the following steps: growing a P-type GaAs buffer layer on a GaAs substrate; growing a P-type GaInP etch stop layer on the P-type GaAs buffer layer; growing a P-type GaAs ohmic contact layer on the P-type GaInP etch stop layer; growing a P-type GaInP electrode bonding layer on the P-type GaAs ohmic contact layer; growing a P-type AlGaInP current spreading layer on the P-type GaInP electrode bonding layer; growing a P-type AlInP confinement layer on the P-type AlGaInP current spreading layer; and growing a P-type AlGaI layer on the P-type AlInP confinement layer. An nP waveguide layer is grown on a P-type AlGaInP waveguide layer. A multi-quantum well layer is grown on the P-type AlGaInP waveguide layer. An N-type AlGaInP waveguide layer is grown on the multi-quantum well layer. An N-type AlInP confinement layer is grown on the N-type AlGaInP waveguide layer. An N-type AlGaInP transition layer is grown on the N-type AlGaInP confinement layer. An N-type GaP superlattice current spreading layer is grown on the N-type AlGaInP transition layer. An N-type GaP ohmic contact layer is grown on the N-type GaP superlattice current spreading layer.

5. The method for fabricating a red micro light-emitting diode epitaxial wafer according to claim 4, characterized in that: Specifically, the steps include: growing a p-type GaAs buffer layer with a thickness of 1500~3000 Å on a GaAs substrate; introducing a p-type doping source, either Cp₂Mg or diethylzinc, with a doping concentration of 1 × 10⁻⁶. 18 ~3×10 18 carriers / cm 3 ; A p-type GaInP etching stop layer with a thickness of 1000~2000 Å is grown, and a p-type doping source is introduced. The doping source is Cp₂Mg or diethylzinc, and the doping concentration is 1× 10⁻⁶. 18 ~3×10 18 carriers / cm 3 ; A p-type GaAs ohmic contact layer with a thickness of 500–800 Å is grown, and a p-type doping source is introduced. The doping source is either Cp₂Mg or diethylzinc, and the doping concentration is >5 × 10⁻⁶. 18 carriers / cm 3 ; A p-type GaInP electrode robust layer with a thickness of 100–500 Å is grown, and a p-type doping source is introduced. The doping source is either Cp₂Mg or diethylzinc, and the doping concentration is 1 × 10⁻⁶. 18 ~3×10 18 carriers / cm 3 ; A p-type AlGaInP current-spreading layer with a thickness of 5000–15000 Å was grown, with an Al composition designed between 0.7 and 1. A p-type doping source was introduced, with the doping source being either Cp₂Mg or diethylzinc, and the doping concentration being 1.5 × 10⁻⁶. 18 ~3×10 18 carriers / cm 3 ; A p-type AlInP confinement layer with a thickness of 2000–4000 Å was grown, and p-type doping was introduced using Cp₂Mg or diethylzinc as the doping source, with a doping concentration of 1 × 10⁻⁶. 18 ~2×10 18 carriers / cm 3 ; A P-type AlGaInP waveguide layer with a thickness of 500~1500 Å was grown, and the Al composition was designed to be between 0.6 and 0.

9. This layer was undoped. A multi-quantum-well layer is grown, wherein the quantum well material is AlGaInP with a thickness of 30-50 Å, the quantum well barrier material is AlGaInP with a thickness of 50-100 Å, the Al composition of the barrier is designed to be 0.6-1, and the number of pairs of potential wells and barriers is 3-8. This layer is undoped. N-type AlGaInP waveguide layers are grown with a thickness of 500~1500 Å and an Al composition designed to be between 0.6 and 0.

9. This layer is undoped. An N-type AlInP confinement layer with a thickness of 2000–3000 Å is grown, and an N-type doping source is introduced. The doping source is either Si₂H₆ or SiH₄, and the doping concentration is 1 × 10⁻⁶. 18 ~2×10 18 carriers / cm 3 ; An N-type AlGaInP transition layer with a thickness of 200–400 Å is grown, and an N-type doping source is introduced. The doping source is Si₂H₆ or SiH₄, and the doping concentration is 4 × 10⁻⁶. 18 ~6×10 18 carriers / cm 3 ; An N-type GaP superlattice current-extended layer is grown. This layer is a periodic composite layer of GaP grown at alternating high and low temperatures: HT-GaP and LT-GaP. The HT-GaP layer is grown at a high temperature of 780–810 °C, with a thickness of 600–1000 Å per layer. The LT-GaP layer is grown at a low temperature of 730–760 °C, with a thickness of 150–250 Å per layer. The temperature difference between the HT-GaP and LT-GaP layers is greater than 50 °C. The number of superlattice composite layers is 20–60 pairs. An N-type doping source, Si₂H₆ or SiH₄, is introduced, with an HT-GaP doping concentration of 3 × 10⁻⁶. 18 ~4×10 18 carriers / cm 3 LT-GaP doping concentration 1× 10 18 ~2×10 18 carriers / cm 3 ; An N-type GaP ohmic contact layer with a thickness of 300–800 Å is grown and an N-type doping source is introduced. The doping source is either Si₂H₆ or SiH₄, and the doping concentration is >5 × 10⁻⁶. 19 carriers / cm 3 .

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