An AlGaN-based detector with integrated optical amplification structure and its preparation method

Abstract

The present invention provides an AlGaN-based detector with an integrated optical amplification structure and a method for preparing the same. The AlGaN-based detector with an integrated optical amplification structure provided by the present invention comprises: an n-type AlGaN cladding, an active layer, a p-type AlGaN cladding, a second p-type GaN layer, a second p-type electrode, a second n-type electrode, a first reflective layer, and a second reflective layer, which constitute the optical amplification structure of the AlGaN-based detector. The AlGaN-based detector with an integrated optical amplification structure of the present invention adds an optical amplification structure to a conventional detector. The AlGaN optical amplification structure is used to amplify incident light. After amplification, the incident light is emitted into the absorption region of the detector, increasing the number of photons entering the absorption region of the detector and improving the gain of the avalanche detector by amplifying the signal light. The present invention is compatible with existing AlGaN avalanche detector structures and has broad application prospects.

Description

Technical Field

[0001] The present invention relates to the field of semiconductor technology, and in particular to an AlGaN-based detector with an integrated light amplification structure and a preparation method thereof. Background Art

[0002] Ultraviolet communication, as a secure and confidential communication method, has garnered widespread attention worldwide. Detector terminals are core components of communication systems, and their performance determines the performance of quantum communication systems. Semiconductor avalanche detectors (APDs), with their compact size, low cost, and ease of operation, have become the preferred solution for ultraviolet detection applications. The ternary alloy AlGaN exhibits a bandgap that continuously varies between 3.4 and 6.2 eV depending on the Al composition, with an absorption wavelength range of 200 to 365 nm, making it an ideal material for ultraviolet and deep ultraviolet detectors.

[0003] To meet the needs of weak signal detection and communication, devices must have ultra-high sensitivity, even requiring the ability to detect single photons, which requires detectors with ultra-high gain. Currently, several research institutions have developed AlGaN APDs, achieving certain breakthroughs and progress in single-photon detection in AlGaN-based ultraviolet and deep ultraviolet detectors. Commonly used APD structures include PIN structures and absorption multiplication and separation structures (SAM structures), which can achieve weak ultraviolet light detection. However, the gain of these devices has not been able to meet practical needs, resulting in low detection efficiency, which has created difficulties in the application of AlGaN APDs.

[0004] Improving material quality and modifying device structure are the primary methods for improving device performance. Improving the crystal quality of the epitaxial layer and reducing the material dislocation density can reduce the device's reverse-bias leakage current. Introducing the polarization effect through reasonable material structure design can effectively increase the device's built-in electric field, regulate the device's avalanche ionization process, and simultaneously reduce the device's operating voltage. However, AlGaN crystals with a high Al content have poor quality, and it is difficult to significantly increase the device's inherent gain through material structure design (primarily utilizing the polarization effect). Excessively thick insertion layers can also increase the detector's response time. Summary of the Invention

[0005] In view of this, the present invention proposes an AlGaN-based detector with an integrated optical amplification structure and a preparation method thereof to solve the technical problems existing in the prior art.

[0006] In a first aspect, the present invention provides an AlGaN-based detector with an integrated optical amplification structure, comprising:

[0007] A substrate, a first n-type AlGaN layer and a second n-type AlGaN layer are provided on the surface of the substrate in an interval;

[0008] A first n-type electrode and a third n-type AlGaN layer are provided on a side of the first n-type AlGaN layer away from the substrate.

[0009] The third n-type AlGaN layer is provided with an i-type AlGaN layer, a p-type AlGaN layer, a first p-type GaN layer, and a first p-type electrode stacked one on the other in sequence on a side away from the substrate;

[0010] An n-type AlGaN cladding layer and a second n-type electrode are provided on a side of the second n-type AlGaN layer away from the substrate.

[0011] The side of the n-type AlGaN cladding layer away from the substrate is provided with an active layer, a p-type AlGaN cladding layer, a second p-type GaN layer, and a second p-type electrode stacked one on the other in sequence;

[0012] a first reflective layer, located on the bottom surface of the substrate and corresponding to the first n-type AlGaN layer;

[0013] A second reflective layer is located on one side of the substrate of the second n-type AlGaN layer. One side of the second reflective layer is in contact with the n-type AlGaN cladding layer, the active layer, the p-type AlGaN cladding layer, and the second p-type GaN layer. The active layer corresponds to the i-type AlGaN layer and is at the same height.

[0014] Preferably, in the AlGaN-based detector with the integrated optical amplification structure, the active layer is an AlGaN active layer, and the AlGaN active layer is a quantum well or quantum dot structure.

[0015] Preferably, in the AlGaN-based detector with the integrated optical amplification structure, the Al mass fraction in the n-type AlGaN cladding layer and the p-type AlGaN cladding layer is greater than the Al mass fraction in the barrier layer of the AlGaN active layer.

[0016] Preferably, in the AlGaN-based detector with an integrated optical amplification structure, the first n-type electrode and the second n-type electrode are Ti / Al / Ti / Au or Ti / Al / Ni / Au.

[0017] Preferably, in the AlGaN-based detector with the integrated optical amplification structure, the first p-type electrode and the second p-type electrode are Ni / Au.

[0018] Preferably, in the AlGaN-based detector with the integrated optical amplification structure, the first reflective layer and the second reflective layer are reflective dielectric layers or reflective metal films.

[0019] Preferably, in the AlGaN-based detector with an integrated optical amplification structure, the reflective dielectric layer is composed of a multi-periodic silicon nitride layer and a silicon dioxide layer;

[0020] The reflective metal film is an Al film.

[0021] Preferably, in the AlGaN-based detector with the integrated optical amplification structure, the distance between the first n-type AlGaN layer and the second n-type AlGaN layer is 5-10 μm.

[0022] Preferably, in the AlGaN-based detector with an integrated optical amplification structure, an AlGaN buffer layer is further provided on the surface of the substrate, and the first n-type AlGaN layer and the second n-type AlGaN layer are spaced apart and arranged on a side of the AlGaN buffer layer away from the substrate;

[0023] And / or, the substrate includes any one of a sapphire substrate provided with an AlN template, a sapphire substrate provided with an AlN template, a silicon substrate provided with an AlN template, a silicon carbide substrate provided with an AlN template, and a GaN substrate provided with an AlN template;

[0024] The first n-type AlGaN layer and the second n-type AlGaN layer are close to one side of the AlN template.

[0025] In a second aspect, the present invention further provides a method for preparing the AlGaN-based detector with the integrated optical amplification structure, comprising the following steps:

[0026] Growing an epitaxial material on a substrate and etching to form a mesa to obtain a first n-type AlGaN layer, a third n-type AlGaN layer, an i-type AlGaN layer, a p-type AlGaN layer, a first p-type GaN layer, and a second n-type AlGaN layer;

[0027] forming a dielectric layer on the first n-type AlGaN layer, the second n-type AlGaN layer, and the first p-type GaN layer;

[0028] Etching the dielectric layer on the second n-type AlGaN layer to expose the regrown region of the optical amplification structure;

[0029] Growing an n-type AlGaN cladding layer, an active layer, a p-type AlGaN cladding layer, and a second p-type GaN layer in the regrown region;

[0030] Etching the first n-type AlGaN layer, the first p-type GaN layer, the second p-type GaN layer, and the dielectric layer outside the regrown region on the second n-type AlGaN layer, and growing a first n-type electrode, a first p-type electrode, a second n-type electrode, and a second p-type electrode;

[0031] growing a first reflective layer on the bottom surface of the substrate;

[0032] A second reflective layer is grown on the second n-type AlGaN layer and is located between the n-type AlGaN cladding layer, the active layer, the p-type AlGaN cladding layer, and the second p-type GaN layer.

[0033] Compared with the prior art, the AlGaN-based detector with an integrated optical amplification structure of the present invention has the following advantages:

[0034] Beneficial effects:

[0035] The AlGaN-based detector with an integrated optical amplifier structure, based on a conventional detector, incorporates an optical amplifier structure. This AlGaN optical amplifier structure amplifies incident light, which then enters the detector's absorption region. This increases the number of photons entering the detector's absorption region, thereby amplifying the signal light and improving the avalanche detector's gain. This invention is compatible with existing AlGaN avalanche detector structures and has broad application prospects. BRIEF DESCRIPTION OF THE DRAWINGS

[0036] To more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are only some embodiments of the present invention. Those skilled in the art can also derive other drawings based on these drawings without inventive effort.

[0037] Figure 1 This is a schematic structural diagram of an AlGaN-based detector with an integrated optical amplification structure according to the present invention;

[0038] Figure 2 This is a schematic flow chart of a method for preparing an AlGaN-based detector with an integrated optical amplification structure according to the present invention. DETAILED DESCRIPTION

[0039] To make the objectives, technical solutions, and advantages of the embodiments of the present invention more apparent, the technical solutions of the embodiments of the present invention will be described clearly and completely below in conjunction with the accompanying drawings of the embodiments of the present invention. It should be understood that the described embodiments are only a portion of the embodiments of the present invention, not all of them. Generally, the components of the embodiments of the present invention described and illustrated in the drawings herein may be arranged and designed in a variety of different configurations.

[0040] Therefore, the following detailed description of the embodiments of the present invention provided in the accompanying drawings is not intended to limit the scope of the invention as claimed, but rather merely represents selected embodiments of the present invention. All other embodiments derived by persons of ordinary skill in the art based on the embodiments of the present invention without creative effort shall fall within the scope of protection of the present invention.

[0041] It should be noted that similar reference numerals and letters denote similar items in the following drawings, and therefore, once an item is defined in one drawing, it does not need to be further defined or explained in subsequent drawings.

[0042] In the description of the present invention, it should be understood that the directions or positions indicated by “upper” and the like are based on the directions or positions shown in the accompanying drawings, or are the directions or positions in which the product of the invention is usually placed when in use, or are the directions or positions commonly understood by those skilled in the art. These directions or positions are only for the convenience of describing the present invention and simplifying the description, and are not intended to indicate or imply that the device or component referred to must have a specific direction, be constructed and operated in a specific direction, and therefore should not be understood as a limitation on the present invention.

[0043] Furthermore, the terms “first”, “second”, etc. are merely used for distinguishing descriptions and should not be understood as indicating or implying relative importance.

[0044] The following will be combined with the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the embodiments described are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of the present invention.

[0045] An AlGaN-based detector with an integrated optical amplification structure, such as Figure 1 As shown, including:

[0046] A substrate 1, on the surface of which a first n-type AlGaN layer 2 and a second n-type AlGaN layer 3 are spaced apart from each other;

[0047] A first n-type AlGaN layer 2 is provided with a first n-type electrode 21 and a third n-type AlGaN layer 22 spaced apart from each other on a side surface away from the substrate;

[0048] The third n-type AlGaN layer 22 has an i-type AlGaN layer 23, a p-type AlGaN layer 24, a first p-type GaN layer 25, and a first p-type electrode 26 stacked one on the side away from the substrate 1;

[0049] The second n-type AlGaN layer 3 is provided with an n-type AlGaN cladding layer 31 and a second n-type electrode 32 spaced apart from each other on a side thereof away from the substrate 1;

[0050] An active layer 33, a p-type AlGaN cladding layer 34, a second p-type GaN layer 35, and a second p-type electrode 36 are sequentially stacked on a side of the n-type AlGaN cladding layer 31 away from the substrate 1;

[0051] A first reflective layer 27 , which is located on the bottom surface of the substrate 1 and corresponds to the first n-type AlGaN layer 2 ;

[0052] The second reflective layer 37 is located on one side of the second n-type AlGaN layer 3 substrate 1. One side of the second reflective layer 37 is in contact with the n-type AlGaN cladding layer 31, the active layer 32, the p-type AlGaN cladding layer 34, and the second p-type GaN layer 35. The active layer 32 corresponds to the i-type AlGaN layer 23 and is at the same height.

[0053] It should be noted that the AlGaN-based detector with an integrated optical amplification structure provided by the present invention comprises: a substrate 1, a first n-type AlGaN layer 2, a second n-type AlGaN layer 3, a third n-type AlGaN layer 22, an i-type AlGaN layer 23, a p-type AlGaN layer 24, a first p-type GaN layer 25, a first p-type electrode 26, and a first n-type electrode 21, which constitute a traditional AlGaN avalanche detector. The third n-type AlGaN layer 22, the i-type AlGaN layer 23, and the p-type AlGaN layer 24 form a PIN structure. ; It also includes: an n-type AlGaN cladding 31, an active layer 33, a p-type AlGaN cladding 34, a second p-type GaN layer 35, a second p-type electrode 36, a second n-type electrode 32, a first reflective layer 27, and a second reflective layer 37, which constitute the optical amplification structure of the AlGaN-based detector; The principle of the AlGaN-based detector with an integrated optical amplification structure of the present invention is: the incident light enters the optical amplification structure of the AlGaN-based detector, and the incident light is amplified and then emitted into the absorption area of ​​the detector, thereby improving the gain of the avalanche detector by amplifying the signal light.

[0054] Specifically, in some embodiments, the first n-type AlGaN layer 2 , the second n-type AlGaN layer 3 , the third n-type AlGaN layer 22 , and the n-type AlGaN cladding layer 31 are all Si-doped n-type AlGaN layers.

[0055] In some embodiments, the p-type AlGaN layer 24 and the p-type AlGaN cladding layer 34 are both Mg-doped p-type AlGaN layers.

[0056] In some embodiments, the first p-type GaN layer 25 and the second p-type GaN layer 35 are both Mg-doped p-type AlGaN layers.

[0057] In some embodiments, the i-type AlGaN layer 23 is undoped AlGaN.

[0058] In some embodiments, the active layer 33 is an AlGaN active layer, which is a quantum structure commonly used in amplifiers, such as a quantum well or a quantum dot.

[0059] Specifically, if the AlGaN active layer is a quantum well structure, then it is Alx Ga 1-x N / A y Ga 1-y N quantum well structure, and x <y,Al x Ga 1-x N is a well layer, Al y Ga 1-y N is a barrier layer, and the Al composition (ie, x value) in the well layer can be changed from 0.05 to 0.9 to meet the needs of devices with different light-emitting wavelengths.

[0060] In some embodiments, the AlGaN active layer includes five periods of quantum wells, and the Al mass fraction in the n-type AlGaN cladding and the p-type AlGaN cladding is greater than the Al mass fraction in the barrier layer in the AlGaN active layer, and the active layer of the amplifying structure and the detector absorption region (i.e., the i-type AlGaN layer 23) are located at the same height.

[0061] Preferably, the Al composition in the well layer of the AlGaN active layer is 0.4, the Al composition in the barrier layer is 0.6, and the Al composition of the n-type AlGaN and p-type AlGaN cladding layers is higher than the Al composition of the well layer of the AlGaN active layer.

[0062] In some embodiments, the first n-type electrode 21 and the second n-type electrode 32 are Ti / Al / Ti / Au or Ti / Al / Ni / Au, wherein Ti / Al / Ti / Au is Ti, Al, Ti, and Au stacked in sequence, and Ti / Al / Ni / Au is Ti, Al, Ni, and Au stacked in sequence.

[0063] In some embodiments, the first p-type electrode 26 and the second p-type electrode 36 are Ni / Au, which is Ni and Au stacked in sequence.

[0064] In some embodiments, the first reflective layer 27 and the second reflective layer 37 are reflective dielectric layers or reflective metal films.

[0065] In some embodiments, the reflective dielectric layer is composed of multiple periods of silicon nitride layers and silicon dioxide layers. Specifically, the reflective dielectric layer is composed of multiple periods of silicon nitride layers and silicon dioxide layers that are alternately arranged in sequence.

[0066] In some embodiments, the reflective metal film is an Al film.

[0067] In some embodiments, the distance between the first n-type AlGaN layer 2 and the second n-type AlGaN layer 3 is 5-10 μm.

[0068] In some embodiments, an AlGaN buffer layer 11 is further provided on the surface of the substrate 1 , and the first n-type AlGaN layer 2 and the second n-type AlGaN layer 3 are spaced apart on a side of the AlGaN buffer layer 11 away from the substrate 1 .

[0069] In some embodiments, the substrate includes any one of a sapphire substrate 1 provided with an AlN template 10 , a sapphire substrate provided with an AlN template 10 , a silicon substrate provided with an AlN template 10 , a silicon carbide substrate provided with an AlN template 10 , and a GaN substrate provided with an AlN template 10 .

[0070] The first n-type AlGaN layer 2 and the second n-type AlGaN layer 3 are close to one side of the AlN template.

[0071] Based on the same inventive concept, the present invention also provides a method for preparing the AlGaN-based detector with the above-mentioned integrated optical amplification structure, such as Figure 2 As shown, the following steps are included:

[0072] S1. Growing an epitaxial material on a substrate and etching to form a mesa to obtain a first n-type AlGaN layer, a third n-type AlGaN layer, an i-type AlGaN layer, a p-type AlGaN layer, a first p-type GaN layer, and a second n-type AlGaN layer;

[0073] S2, forming a dielectric layer on the first n-type AlGaN layer, the second n-type AlGaN layer, and the first p-type GaN layer;

[0074] S3, etching the dielectric layer on the second n-type AlGaN layer to expose the regrown area of ​​the optical amplification structure;

[0075] S4, growing an n-type AlGaN cladding layer, an active layer, a p-type AlGaN cladding layer, and a second p-type GaN layer in the regrown region;

[0076] S5, etching the first n-type AlGaN layer, the first p-type GaN layer, the second p-type GaN layer, and the dielectric layer outside the regrown region on the second n-type AlGaN layer, and growing a first n-type electrode, a first p-type electrode, a second n-type electrode, and a second p-type electrode;

[0077] S6, growing a first reflective layer on the bottom surface of the substrate;

[0078] S7 , growing a second reflective layer on the second n-type AlGaN layer and located on the n-type AlGaN cladding layer, the active layer, the p-type AlGaN cladding layer, and the second p-type GaN layer.

[0079] Specifically, in step S1, an epitaxial material is grown on a substrate, and the specific epitaxial material is n-type AlGaN, undoped AlGaN, p-type AlGaN, and p-type GaN, and the growth method is metal organic compound vapor deposition (MOCVD) or molecular beam epitaxy (MBE); a photoresist or silicon oxide is used as a mesa mask to perform mesa etching to form a first n-type AlGaN layer, a third n-type AlGaN layer, an i-type AlGaN layer, a p-type AlGaN layer, and a first p-type GaN layer of the detector; then, the n-AlGaN layer of the optical amplification structure area of ​​the detector is etched to ensure that the detector absorption layer (i.e., the i-type AlGaN layer) and the active layer can be aligned, and finally a second n-type AlGaN layer is obtained.

[0080] Specifically, in step S2, based on step S1, the entire device is plated with a dielectric layer mask, wherein the dielectric layer coating is performed using PECVD or ALD technology, and finally a dielectric layer is generated on the first n-type AlGaN layer, the second n-type AlGaN layer, and the first p-type GaN layer; the dielectric layer film is generally silicon oxide or silicon nitride; and the thickness of the dielectric layer is 200 to 400 nm.

[0081] In step S3, the dielectric layer on the second n-type AlGaN layer is etched to expose the optical amplification structure regrowth area, so as to grow the n-type AlGaN cladding layer, active layer, p-type AlGaN cladding layer, and second p-type GaN layer of the optical amplification structure;

[0082] In step S4, metal organic chemical vapor deposition (MOCVD) or molecular beam epitaxy (MBE) is used to grow an n-type AlGaN cladding layer, an active layer, a p-type AlGaN cladding layer, and a second p-type GaN layer in the regrown region.

[0083] In step S5, based on step S4, the dielectric layer on the device is etched to expose the growth areas corresponding to the first n-type electrode, the first p-type electrode, the second n-type electrode, and the second p-type electrode. The first n-type electrode, the first p-type electrode, the second n-type electrode, and the second p-type electrode are then grown. Specifically, the first n-type electrode, the first p-type electrode, the second n-type electrode, and the second p-type electrode are formed by electron beam evaporation or thermal evaporation. During the preparation process, an annealing process is selected according to the type of metal electrode. If the first n-type electrode 21 and the second n-type electrode 32 are Ti / Al / Ti / Au or Ti / Al / Ni / Au, the annealing temperature is 600-800°C; if the first p-type electrode 26 and the second p-type electrode 36 are Ni / Au, the annealing temperature is 400-600°C.

[0084] In steps S6 to S7, the selection of the first reflective layer and the second reflective layer should match the operating wavelength of the device, and the types include but are not limited to high-reflectivity metal and dielectric layers, and the dielectric layer of the photonic crystal structure wall (the dielectric layer is composed of a multi-period silicon nitride layer and a silicon dioxide layer); by plating a high-reflectivity layer on the back of the substrate and the sidewalls of the amplifier structure, and then removing the high-reflectivity layer on the back of the amplifier and the light-emitting sidewall; or, using photolithography to obtain a mask pattern, using a mask to plate a high-reflectivity layer only on the back of the detector and the non-light-emitting sidewall of the amplifier.

[0085] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the scope of protection of the present invention.

Claims

1. An AlGaN-based detector with an integrated optical amplification structure, characterized in that: include: A substrate, a first n-type AlGaN layer and a second n-type AlGaN layer are provided on the surface of the substrate in an interval; A first n-type electrode and a third n-type AlGaN layer are provided on a surface of the first n-type AlGaN layer away from the substrate. The surface of the third n-type AlGaN layer away from the substrate is provided with an i-type AlGaN layer, a p-type AlGaN layer, a first p-type GaN layer, and a first p-type electrode stacked one on the other in sequence; The second n-type AlGaN layer is separated from the substrate by an n-type AlGaN cladding layer. a second n-type electrode; The surface of the n-type AlGaN cladding layer away from the substrate is provided with an active layer, a p-type AlGaN cladding layer, a second p-type GaN layer, and a second p-type electrode stacked one on the other in sequence; a first reflective layer, located on the bottom surface of the substrate and corresponding to the first n-type AlGaN layer; A second reflective layer is located on a side of the second n-type AlGaN layer away from the substrate, one side of the second reflective layer is in contact with the n-type AlGaN cladding layer, the active layer, the p-type AlGaN cladding layer, and the second p-type GaN layer, and the active layer corresponds to the i-type AlGaN layer and is at the same height.

2. The AlGaN-based detector with an integrated optical amplification structure according to claim 1, wherein: The active layer is an AlGaN active layer, and the AlGaN active layer is a quantum well or quantum dot structure.

3. The AlGaN-based detector with an integrated optical amplification structure according to claim 2, wherein: The Al mass fraction in the n-type AlGaN cladding layer and the p-type AlGaN cladding layer is greater than the Al mass fraction in the barrier layer of the AlGaN active layer.

4. The AlGaN-based detector with an integrated optical amplification structure according to claim 1, wherein: The first n-type electrode and the second n-type electrode are Ti / Al / Ti / Au or Ti / Al / Ni / Au.

5. The AlGaN-based detector with an integrated optical amplification structure according to claim 1, wherein: The first p-type electrode and the second p-type electrode are Ni / Au.

6. The AlGaN-based detector with an integrated optical amplification structure according to claim 1, wherein: The first reflective layer and the second reflective layer are reflective dielectric layers or reflective metal films.

7. The AlGaN-based detector with an integrated optical amplification structure according to claim 6, characterized in that: The reflective dielectric layer is composed of a multi-periodic silicon nitride layer and a silicon dioxide layer; The reflective metal film is an Al film.

8. The AlGaN-based detector with an integrated optical amplification structure according to claim 1, wherein: The distance between the first n-type AlGaN layer and the second n-type AlGaN layer is 5-10 μm.

9. The AlGaN-based detector with an integrated optical amplification structure according to any one of claims 1 to 8, characterized in that: An AlGaN buffer layer is further provided on the surface of the substrate, and the first n-type AlGaN layer and the second n-type AlGaN layer are alternately provided on a side of the AlGaN buffer layer away from the substrate; And / or, the substrate includes any one of a sapphire substrate provided with an AlN template, a sapphire substrate provided with an AlN template, a silicon substrate provided with an AlN template, a silicon carbide substrate provided with an AlN template, and a GaN substrate provided with an AlN template; The first n-type AlGaN layer and the second n-type AlGaN layer are close to one side of the AlN template.

10. A method for preparing an AlGaN-based detector with an integrated optical amplification structure according to any one of claims 1 to 9, characterized in that: The following steps are involved: Growing an epitaxial material on a substrate and etching to form a mesa to obtain a first n-type AlGaN layer, a third n-type AlGaN layer, an i-type AlGaN layer, a p-type AlGaN layer, a first p-type GaN layer, and a second n-type AlGaN layer; forming a dielectric layer on the first n-type AlGaN layer, the second n-type AlGaN layer, and the first p-type GaN layer; Etching the dielectric layer on the second n-type AlGaN layer to expose the regrown region of the optical amplification structure; Growing an n-type AlGaN cladding layer, an active layer, a p-type AlGaN cladding layer, and a second p-type GaN layer in the regrown region; Etching the first n-type AlGaN layer, the first p-type GaN layer, the second p-type GaN layer, and the dielectric layer outside the regrown region on the second n-type AlGaN layer, and growing a first n-type electrode, a first p-type electrode, a second n-type electrode, and a second p-type electrode; growing a first reflective layer on the bottom surface of the substrate; A second reflective layer is grown on the second n-type AlGaN layer and is located between the n-type AlGaN cladding layer, the active layer, the p-type AlGaN cladding layer, and the second p-type GaN layer.

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