Surface emitting laser and method for manufacturing the same, light emitting assembly, and optical module

Abstract

This application relates to surface-emitting lasers and their fabrication methods, optical emitting components, and optical modules. The fabrication method includes: providing an epitaxial wafer, the epitaxial wafer including a substrate and an epitaxial layer formed on the substrate; forming a photochromic pattern on the side of the epitaxial layer facing away from the substrate; performing mesa etching on the epitaxial layer under the masking of the photochromic pattern; wherein a chlorine-based gas is used as the reactant gas, and the epitaxial layer is etched in a direction perpendicular to the epitaxial wafer under preset etching process parameters; monitoring the etching depth during the etching process and plotting an etching curve; after reaching the preset depth, adjusting the current etching process parameters so that the angle between the etched mesa and the substrate is an obtuse angle; after etching, placing the mesa at a preset temperature and baking for a preset time. The solution of this application can achieve damage-free ICP etching and controllable etching angle, facilitating subsequent metal deposition and lift-off processes and improving product performance.

Description

Technical Field

[0001] This application relates to the field of semiconductor laser technology, and in particular to a method for preparing a surface-emitting laser and a surface-emitting laser. Background Technology

[0002] Surface-emitting lasers, such as vertical-cavity surface-emitting lasers (VCSELs), have become the preferred light source for short-distance optical interconnects due to their advantages such as high modulation speed, easy coupling with optical fibers, and low power consumption. They are the most critical technology determining the single-channel rate of optical modules. The core challenge in improving their transmission rate lies in achieving a synergistic solution among the interdependent factors that require high differential gain, low carrier transport factor, precise matching of microcavity damping, and thermal effect management to achieve both reliability and rate improvement.

[0003] Current ICP etching processes pre-configure etching parameters before etching and then proceed with the etching process until it is complete. However, this fixed etching method can damage the VCSEL, and the angle of the etched mesa is uncontrollable. Summary of the Invention

[0004] Therefore, it is necessary to provide a method for fabricating a surface-emitting laser and a surface-emitting laser in response to the above-mentioned technical problems.

[0005] In a first aspect, this application provides a method for fabricating a surface-emitting laser, comprising:

[0006] An epitaxial wafer is provided, the epitaxial wafer including a substrate and an epitaxial layer formed on the substrate;

[0007] A photochromic pattern is formed on the side of the epitaxial layer opposite to the substrate;

[0008] Mesa etching is performed on the epitaxial layer under the masking of the photochromic pattern; wherein, chlorine-based gas is used as the reaction gas, and the epitaxial layer is etched in a direction perpendicular to the epitaxial wafer under preset etching process parameters;

[0009] The etching depth during the etching process is monitored and an etching curve is plotted. After the preset depth is reached, the current etching process parameters are adjusted so that the angle between the etched mesa and the substrate is an obtuse angle.

[0010] After etching is completed, the platform is placed at a preset temperature and baked for a preset time.

[0011] It is understood that, in this embodiment, a photochromic pattern is formed on the side of the epitaxial layer facing away from the substrate, and then mesa etching is performed on the epitaxial layer under the cover of the photochromic pattern. Chlorine-based gas is used as the reactant gas, and the epitaxial layer is etched in a direction perpendicular to the epitaxial wafer under preset etching process parameters. The etching depth is monitored during the etching process, and an etching curve is plotted. After reaching the preset depth, the current etching process parameters are adjusted so that the angle between the etched mesa and the substrate is obtuse. After etching, the mesa is baked at a preset temperature for a preset time. This allows for real-time monitoring of the etching depth during etching to change the etching process parameters, effectively reducing etching damage and facilitating the control of the etching angle. Finally, baking is used to repair damage, further reducing etching damage and improving product performance.

[0012] In one possible embodiment, before forming a photochromic pattern on the side of the epitaxial layer opposite to the substrate, the method further includes:

[0013] Proton implantation is performed on the side of the epitaxial layer opposite to the substrate to form a proton implantation region;

[0014] After proton implantation, a first metal electrode is deposited on the surface of the epitaxial layer opposite to the substrate.

[0015] In one possible embodiment, the epitaxial layer includes a bottom mirror structure, an active layer, and a top mirror structure sequentially disposed; the mesa etching of the epitaxial layer under the masking of the photochromic pattern includes:

[0016] The proton injection region is etched under the cover of the photochromic pattern to expose part of the bottom mirror structure, forming an oxide trench;

[0017] The etched epitaxial layer is subjected to wet oxygen treatment through the oxide trenches to oxidize the high-Al layer in the top mirror structure to form an oxide confinement layer.

[0018] In one possible embodiment, the preset etching process parameters include: the power of the ICP etching equipment is 150W, and the introduced gas includes BCl3, Cl2 and Ar; the flow rate of BCl3 is 30 sccm, the flow rate of Cl2 is 10 sccm, and the flow rate of Ar is 12 sccm.

[0019] In one possible embodiment, the obtuse angle is in the range of [100°, 120°].

[0020] In one possible embodiment, the method further includes:

[0021] The bottom reflector structure is subjected to mesa etching to expose a portion of the substrate.

[0022] In one possible embodiment, the method further includes:

[0023] A second metal electrode is deposited on the exposed substrate.

[0024] Secondly, this application provides a surface-emitting laser, comprising:

[0025] Substrate;

[0026] The substrate has a bottom reflector structure and a second metal electrode located around the bottom reflector structure; the bottom reflector structure includes a first bottom reflector structure and a second bottom reflector structure, and the first bottom reflector structure makes an obtuse angle with the substrate;

[0027] An active layer is disposed on the first bottom reflector structure via a second bottom reflector structure; the diameter of the second bottom reflector structure is the same as the diameter of the active layer, and the diameter of the second bottom reflector structure is smaller than the diameter of the first bottom reflector structure.

[0028] A top reflector structure is located on the active layer and has the same diameter as the active layer. The top reflector structure includes an oxidation confinement layer that is close to the active layer.

[0029] The first metal electrode is disposed on the top reflector structure.

[0030] Thirdly, this application provides a light emitting component, including at least one surface-emitting laser as described above.

[0031] Fourthly, this application provides an optical module, including an optical emitting module and an optical receiving module, wherein the optical emitting module is the aforementioned optical emitting component. Attached Figure Description

[0032] Figure 1 This is a schematic flowchart of a method for fabricating a surface-emitting laser according to an embodiment of this application;

[0033] Figure 2 for Figure 1 A schematic diagram of the epitaxial wafer structure in the fabrication method of the surface-emitting laser shown;

[0034] Figure 3 for Figure 1 The schematic diagram shows the structure after proton injection and the formation of the first metal electrode in the fabrication method of the surface-emitting laser shown.

[0035] Figure 4 for Figure 1 The schematic diagram shows the structure of the surface-emitting laser after P-mesa etching in the fabrication method of the surface-emitting laser shown.

[0036] Figure 5 for Figure 1 The diagram shows a structural schematic of the second mesa etching process in the fabrication method of the surface-emitting laser shown.

[0037] Figure 6 for Figure 1 A schematic diagram of the structure after the second metal electrode is formed in another embodiment of the fabrication method of the surface-emitting laser shown;

[0038] Figure 7 This is a schematic diagram of the surface-emitting laser provided in this embodiment.

[0039] The objectives, features, and advantages of this invention will be further explained in conjunction with the embodiments and with reference to the accompanying drawings. Detailed Implementation

[0040] To make the objectives, technical solutions, and advantages of this application clearer, the following detailed description is provided in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the scope of this application.

[0041] It is understood that the terms "first," "second," etc., used in this application may be used herein to describe various elements, but these elements are not limited by these terms. These terms are only used to distinguish one element from another. For example, without departing from the scope of this application, a first client may be referred to as a second client, and similarly, a second client may be referred to as a first client.

[0042] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one of that feature. "Multiple" means at least two, such as two, three, etc., unless otherwise explicitly specified. "Several" means at least one, such as one, two, etc., unless otherwise explicitly specified.

[0043] Based on this, this application creatively proposes a method for fabricating a surface-emitting laser, aiming to solve the aforementioned technical problems.

[0044] Firstly, such as Figure 1 As shown, this application provides a method for fabricating a surface-emitting laser, the method comprising:

[0045] Step S101: Provide an epitaxial wafer.

[0046] The epitaxial wafer includes a substrate and an epitaxial layer formed on the substrate.

[0047] like Figure 2 As shown, in one possible embodiment, the epitaxial layer includes a bottom mirror structure 110, an active layer 120, and a top mirror structure 130 arranged sequentially.

[0048] In this embodiment, the bottom reflector structure 110 and the top reflector structure 130 define the resonant cavity structure of the vertical cavity surface-emitting laser of this application; that is, the region between the bottom reflector structure 110 and the top reflector structure 130 is the resonant cavity. The resonant cavity is used to generate standing waves, which are waves formed by two coherent waves propagating in opposite directions along the same straight line and superimposing on each other. Specifically, when the two waves are in phase, their amplitudes are added together to form antinodes (i.e., wave crests). When the two waves are out of phase, their amplitudes are subtracted to form nodes (i.e., wave troughs). Therefore, the positions of the wave crests and troughs of the standing wave are fixed.

[0049] In one embodiment, the bottom mirror structure 110 may include a periodically stacked DBR structure, i.e., multiple mirrors with an optical thickness of one-quarter of the lasing wavelength, arranged alternately with high and low refractive indices. The top mirror structure 130 also includes a periodically stacked DBR structure, i.e., multiple mirrors with an optical thickness of one-quarter of the lasing wavelength, arranged alternately with high and low refractive indices. It is understood that the composition, stacking period number, etc., of the DBR structure of the bottom mirror structure 110 and the DBR structure of the top mirror structure 130 may be the same or different; this embodiment does not impose limitations. The materials of the top mirror structure 130 and the bottom mirror structure 110 may be electrically insulating dielectric materials, such as silicon nitride, silicon oxide, aluminum oxide, or titanium oxide. The materials of the top mirror structure 130 and the bottom mirror structure 110 may also be semiconductor materials, such as GaAs and AlGaAs.

[0050] The substrate 10 is made of materials including, but not limited to, GaAs, InP, and Si. The bottom mirror structure 110 and the top mirror structure 130 may include films with periodically varying refractive indices to achieve efficient reflection or transmission of light within a specific wavelength range. These films can be made of semiconductor materials, dielectric materials, or metal-dielectric hybrid materials. For example, the bottom mirror structure 110 may be an N-type semiconductor layer, and the top mirror structure 130 may be a P-type semiconductor layer. Alternatively, the bottom mirror structure 110 may be a P-type semiconductor layer, and the top mirror structure 130 may be an N-type semiconductor layer. Optionally, the materials of the N-type and P-type semiconductor layers may be, but are not limited to, GaAs, AlGaAs, etc. This is not a limitation; as long as the resonant cavity can be defined, it falls within the scope of this embodiment.

[0051] The active layer 120 may include one, two, three, or four active regions. Each active region may contain one or more multi-quantum-well structures. The multi-quantum-well structures are used to generate photons through stimulated emission, and the emitted photons are continuously reflected in the resonant cavity defined by the bottom mirror structure 110 and the top mirror structure 130, and are continuously amplified during the reflection process, thereby ultimately emitting laser light at a specific wavelength with sufficient energy.

[0052] The multiple quantum well structure is where laser gain amplification occurs. The center of the multiple quantum well structure can be aligned with the location of the strongest light field to achieve a greater amplification effect. Furthermore, when multiple multiple quantum well structures are included, their confinement factors within the same light field segment are within the same preset range; that is, the confinement factors of each multiple quantum well structure are maintained at the same level, ensuring that each multiple quantum well structure contributes similarly to the light emission. Understandably, similar light emission contributions mean more uniform current injection into each multiple quantum well structure, which helps reduce the device's threshold current, thereby reducing power consumption and extending its lifespan. Moreover, when each multiple quantum well structure contributes similarly to the light emission, the distribution of charge carriers within each multiple quantum well structure will be more uniform, which helps reduce carrier recombination losses, thereby improving the overall luminous efficiency of the device.

[0053] Step S102: A photochromic pattern is formed on the side of the epitaxial layer opposite to the substrate.

[0054] In one possible embodiment, prior to step S102, the fabrication method further includes: performing proton implantation on the side of the epitaxial layer away from the substrate to form a proton implantation region; and depositing a first metal electrode on the surface of the epitaxial layer away from the substrate after proton implantation.

[0055] For example, such as Figure 3 As shown, proton implantation is performed on the side of the epitaxial layer away from the substrate to form a proton implantation region 133. After proton implantation, a first metal electrode 150 is deposited on the surface of the epitaxial layer away from the substrate. The first metal electrode 150 is located within the proton implantation region 133.

[0056] Optionally, the first metal electrode 150 can be a P-type electrode or an N-type electrode. In this embodiment, the following description will use a P-type electrode as the first metal electrode.

[0057] It is understandable that protons are first injected at the edge of the P-type mesa to insulate the edge of the mesa and form a proton injection region, so that the proton injection region can be etched subsequently, so as to etch the top reflector structure.

[0058] In one implementation, the first metal electrode can be formed by depositing a P-type ohmic contact metal layer on the surface of the top reflector structure using a photolithography lift-off process. The metal layer structure is Ti / Pt / Au, and the deposition method is electron beam evaporation.

[0059] Step S103: Mesa etching is performed on the epitaxial layer under the cover of the photochromic pattern.

[0060] In this process, chlorine-based gas is used as the reaction gas, and the epitaxial layer is etched in a direction perpendicular to the epitaxial wafer under preset etching process parameters.

[0061] As one implementation, step S103 includes: etching the proton injection region under the masking of the photochromic pattern to expose part of the bottom mirror structure and form an oxide trench; performing wet oxygen treatment on the etched epitaxial layer through the oxide trench to oxidize the high-Al layer in the top mirror structure to form an oxide confinement layer.

[0062] For example, when etching the proton injection region, the etching can be stopped after several cycles (such as one or two cycles, or even multiple cycles) of the bottom mirror structure. In order to obtain VCSELs with different oxide pore sizes, the diameter of the P-type mesa is selected to be 27cm~36cm.

[0063] Optionally, the preset etching process parameters include: the power of the ICP etching equipment is 150W, and the introduced gas includes BCl3, Cl2 and Ar; the flow rate of BCl3 is 30 sccm, the flow rate of Cl2 is 10 sccm, and the flow rate of Ar is 12 sccm.

[0064] Optionally, the preset etching process parameters also include: radio frequency power, i.e., RF: 150W.

[0065] For example, such as Figure 4 As shown, a P-type mesa is formed by etching the proton implantation region 133 so that the angle between the etched mesa and the substrate 10 is an obtuse angle α, and the high Al layer is completely exposed. Then the product is placed in a wet oxygen oxidation furnace, and N2 carries the oxidant H2O vapor to react with the high Al layer to form an oxidation confinement layer 131.

[0066] Step S104: Monitor the etching depth during the etching process and plot the etching curve. After reaching the preset depth, adjust the current etching process parameters so that the angle between the etched mesa and the substrate is an obtuse angle.

[0067] Optionally, the etching depth can be monitored and an etching curve can be plotted using an in-situ reflectivity measurement system, so that the positions of the bottom mirror structure, the active layer, the top mirror structure, and the substrate can be clearly distinguished based on the etching curve.

[0068] Optionally, the obtuse angle can be in the range of [100°, 120°]. For example, the formed obtuse angle can be 100°, 106°, 110°, or 120°, etc.

[0069] Step S105: After etching is completed, the platform is placed at a preset temperature and baked for a preset time.

[0070] Optionally, the preset temperature can be 150°.

[0071] Optionally, the preset time can be 5 minutes.

[0072] Of course, in other embodiments, the preset temperature may be greater than or less than 150°C, and the preset baking time may also be adjusted according to product requirements. No specific limitations are made here.

[0073] In one possible embodiment, after step S105, the fabrication method further includes: performing mesa etching on the bottom mirror structure to expose a portion of the substrate.

[0074] It is understandable that after the P-mesa etching is completed, a second mesa etching (i.e., etching of the bottom reflector structure) is performed using plasma reactive ion etching (ICP) and chlorine-based plasma processes.

[0075] The chlorine-based plasma process can be referenced from the process of the first mesa etching, and will not be elaborated here.

[0076] In one possible embodiment, after step S105, the preparation method further includes: forming a passivation layer on the substrate.

[0077] Alternatively, the passivation layer can be made of SiN or SiO, etc.

[0078] It is understandable that passivation layers can be achieved by depositing SiN films using PECVD.

[0079] For example, such as Figure 5 As shown, a second mesa etching is performed on the bottom reflector structure 110 to expose a portion of the substrate 10.

[0080] In one possible embodiment, the fabrication method further includes: depositing a second metal electrode on the exposed substrate.

[0081] Optionally, the second metal electrode is an N-type electrode.

[0082] For example, such as Figure 6 As shown, a SiN film (i.e., passivation layer 160) is deposited by PECVD for passivation. Then, electrode holes are opened on the surface of the N region by means of opening holes. Then, an N-type ohmic contact metal layer (second metal electrode 140) is deposited on the surface of the N region. The metal layer structure is Au / Ge / Ni / Au. The deposition method is electron beam evaporation and rapid thermal annealing to form an ohmic alloy.

[0083] In one possible embodiment, the fabrication method further includes: forming a planarization layer on an epitaxial wafer, the planarization layer covering the first metal electrode and the second metal electrode.

[0084] For example, BCB low dielectric constant material was spin-coated onto the surface of an epitaxial wafer and planarized under high temperature and nitrogen atmosphere. The thickness of the BCB after curing was monitored using a profilometer and SEM.

[0085] In one possible embodiment, the fabrication method further includes removing excess BCB from the P-meta-plate using processes such as photolithography and etching.

[0086] In one possible embodiment, the preparation method further includes removing excess BCB on the second metal electrode using processes such as photolithography and etching.

[0087] In one possible embodiment, the preparation method further includes: sputtering and electroplating a metal seed layer on the surface of a surface-emitting laser; defining the area to be electroplated on the metal seed layer by contact exposure and projection; drawing out N and P electrodes in the electroplating area by chemical electroplating; and removing the remaining metal seed layer on the surface of the surface-emitting laser by wet chemical etching.

[0088] It is understood that the surface-emitting laser fabrication method provided in this embodiment can effectively reduce etching damage and further reduce leakage current by optimizing the etching process, and the tilt angle of the mesa can be adjusted to facilitate the subsequent metal deposition and stripping process, thereby improving product performance.

[0089] like Figure 7 As shown, in one embodiment, this application also provides a surface-emitting laser, including a substrate 10;

[0090] The substrate 10 is provided with a bottom reflector structure 110 and a second metal electrode 140 located around the bottom reflector structure 110; the bottom reflector structure 110 includes a first bottom reflector structure 111 and a second bottom reflector structure 113, and the angle between the first bottom reflector structure 111 and the substrate 10 is an obtuse angle.

[0091] An active layer 120 is provided on the first bottom reflector structure 111 via a second bottom reflector structure 113; the diameter of the second bottom reflector structure 113 is the same as the diameter of the active layer 120, and the diameter of the second bottom reflector structure 113 is smaller than the diameter of the first bottom reflector structure 111.

[0092] A top reflector structure 130 is located on the active layer 120, and the top reflector structure 130 has the same diameter as the active layer 120. The top reflector structure 130 includes an oxidation confinement layer 131, which is close to the active layer 120.

[0093] The first metal electrode 150 is disposed on the top reflector structure 130.

[0094] It should be noted that the fabrication process of this surface-emitting laser can be referred to the description of the above method embodiments, and will not be repeated here.

[0095] In one embodiment, this application also provides a light emitting component, which includes at least one surface-emitting laser.

[0096] In one embodiment, this application also provides an optical module including at least one optical emitting component as described above.

[0097] The foregoing disclosure provides illustrations and descriptions, but is not intended to be exhaustive or to limit the embodiments to the precise forms disclosed. Modifications and variations may be made in light of the foregoing disclosure or may be derived from practice of the embodiments. Furthermore, any embodiments described herein may be combined unless the foregoing disclosure expressly provides for reasons why one or more embodiments may not be combined.

[0098] Even though specific combinations of features are listed in the claims and / or disclosed in the specification, these combinations are not intended to limit the disclosure of the various embodiments. In fact, many of these features can be combined in ways not specifically listed in the claims and / or disclosed in the specification. Although each dependent claim listed below may directly depend on only one claim, the disclosure of the various embodiments includes each dependent claim combined with each other claim in the claim set. As used herein, the phrase “at least one of” in the list of items refers to any combination of these items, including a single member. As an example, “at least one of: a, b, or c” is intended to cover a, b, c, ab, ac, bc, and abc, as well as any combination having multiple identical items.

[0099] When a component or one or more components (e.g., a laser emitter or one or more laser emitters) is described or required (within a single claim or across multiple claims) to perform or be configured to perform multiple operations, this language is intended to broadly cover a wide range of architectures and environments. For example, unless explicitly required otherwise (e.g., by using “first component” and “second component” or other language distinguishing components in the claims), this language is intended to cover a single component performing or configured to perform all operations, a group of components jointly performing or configured to perform all operations, a first component performing or configured to perform a first operation and a second component performing or configured to perform a second operation, or any combination of components performing or configured to perform operations. For example, when a claim takes the form “one or more components are configured to: perform X; perform Y; and perform Z,” the claim should be interpreted as meaning “one or more components are configured to perform X; one or more (possibly different) components are configured to perform Y; and one or more (possibly different) components are configured to perform Z.”

[0100] The elements, actions, or instructions used herein should not be construed as critical or necessary unless explicitly stated otherwise. Furthermore, as used herein, the articles “a” and “one” are intended to include one or more items and may be used interchangeably with “one or more.” Further, as used herein, the article “the” is intended to include one or more items referenced in combination with the article “the” and may be used interchangeably with “the one or more.” Additionally, as used herein, the term “set” is intended to include one or more items (e.g., related items, unrelated items, or a combination of related and unrelated items) and may be used interchangeably with “one or more.” Where only one item is intended, the phrase “only one” or similar language is used. Furthermore, as used herein, the terms “having,” “containing,” “with,” etc., are intended to be open-ended terms. Further, unless explicitly stated otherwise, the phrase “based on” is intended to mean “at least partially based on.” Furthermore, as used herein, unless otherwise expressly stated (e.g., when used in combination with “any one” or “only one of”), the term “or” is intended to be inclusive when used in series and can be used interchangeably with “and / or”. Further, for ease of description, spatially relative terms such as “below,” “lower,” “above,” “upper,” etc., may be used herein to describe the relationship of an element or feature to another element(s) or feature(s) illustrated in the accompanying drawings. In addition to the orientations depicted in the accompanying drawings, spatially relative terms are intended to cover different orientations of devices, apparatuses, and / or elements in use or operation. The device may be oriented in other ways (rotated 90 degrees or otherwise), and the spatially relative descriptors used herein shall be interpreted accordingly.

Claims

1. A method for fabricating a surface-emitting laser, characterized in that, include: An epitaxial wafer is provided, the epitaxial wafer including a substrate and an epitaxial layer formed on the substrate; A photochromic pattern is formed on the side of the epitaxial layer opposite to the substrate; Mesa etching is performed on the epitaxial layer under the masking of the photochromic pattern; wherein, chlorine-based gas is used as the reactant gas, and the epitaxial layer is etched in a direction perpendicular to the epitaxial wafer under preset etching process parameters, the preset etching process parameters including: the power of the ICP etching equipment is 150W, the introduced gas includes BCl3, Cl2 and Ar; the flow rate of BCl3 is 30 sccm, the flow rate of Cl2 is 10 sccm, and the flow rate of Ar is 12 sccm; The etching depth during the etching process is monitored in real time and an etching curve is plotted using an in-situ reflectivity measurement system. After reaching the preset depth, the current etching process parameters are dynamically adjusted based on the etching curve so that the angle between the etched mesa and the substrate is an obtuse angle, and the value range of the obtuse angle is [100°, 120°]. After etching is completed, the mesa is baked at 150°C for 5 minutes to repair the damage caused by etching.

2. The method for fabricating a surface-emitting laser according to claim 1, characterized in that, Before forming a photochromic pattern on the side of the epitaxial layer facing away from the substrate, the method further includes: Proton implantation is performed on the side of the epitaxial layer opposite to the substrate to form a proton implantation region; After proton implantation, a first metal electrode is deposited on the surface of the epitaxial layer opposite to the substrate.

3. The method for fabricating a surface-emitting laser according to claim 2, characterized in that, The epitaxial layer includes a bottom mirror structure, an active layer, and a top mirror structure arranged sequentially; the mesa etching of the epitaxial layer under the masking of the photochromic pattern includes: The proton injection region is etched under the cover of the photochromic pattern to expose part of the bottom mirror structure, forming an oxide trench; The etched epitaxial layer is subjected to wet oxygen treatment through the oxide trenches to oxidize the high-Al layer in the top mirror structure to form an oxide confinement layer.

4. The method for fabricating a surface-emitting laser according to claim 3, characterized in that, The method further includes: The bottom reflector structure is subjected to mesa etching to expose a portion of the substrate.

5. The method for fabricating a surface-emitting laser according to claim 4, characterized in that, The method further includes: A second metal electrode is deposited on the exposed substrate.

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