Vertical-cavity surface-emitting laser array with microchannels and preparation method of vertical-cavity surface-emitting laser array

Abstract

The invention provides a vertical cavity surface emitting laser array with micro-channels, which can be applied to the technical field of semiconductor lasers. The laser array comprises a substrate which is provided with a first surface and a second surface which are oppositely arranged; the functional structure layer is located on the first surface and comprises N vertical cavity surface emitting laser units and a micro-channel; the cover layer is located on the side, away from the substrate, of the functional structure layer; the first electrode is located on the second surface. Wherein the N vertical cavity surface emitting laser units are arranged in an array according to a preset interval, and a laser array with grooves is obtained; and at least one part of the micro-channel is arranged in a channel formed by the groove and the cover layer. The micro-channels are arranged between the adjacent laser array units, so that the cooling working medium can directly flow through the heat source of the laser, the laser array is directly cooled, and the heat dissipation efficiency is improved. The invention also provides a preparation method of the vertical cavity surface emitting laser array with the micro-channel.

Description

Technical Field

[0001] The present invention relates to the technical field of semiconductor lasers, and in particular to a vertical cavity surface emitting laser array with microchannels and a preparation method thereof. Background Art

[0002] Vertical-cavity surface-emitting laser (VCSEL) has the characteristics of small size, low threshold and easy two-dimensional integration. After integrating VCSEL into a high-power array, it can be applied to laser radar, infrared lighting, solid laser pumping and other fields.

[0003] VCSEL arrays for high-power applications have a very high thermal power density when working, so passive or active heat dissipation is required. Passive heat dissipation often requires a large metal heat sink, which hinders the miniaturization of the device and limits its working performance. In the current active heat dissipation technology, microchannel heat sinks are usually placed under the substrate for heat dissipation. Microchannels have high heat dissipation efficiency and can complete high-power heat exchange in a very small area.

[0004] However, since VCSEL is formed by growing multilayer film structures such as distributed Bragg reflectors (DBRs) and active regions on semiconductor materials, heat is mainly generated by the active region. The thermal conductivity of the semiconductor material forming the VCSEL is low, and the scattering of phonons by the interlayer interface of the multilayer film greatly increases the thermal resistance of the device. Therefore, even if a microchannel heat sink is placed under the substrate of the VCSEL array, a large temperature gradient will be generated between the microchannel and the active region, causing the device to operate at a higher temperature. Summary of the invention

[0005] 1. Technical issues to be resolved

[0006] In order to solve at least one of the above-mentioned technical problems arising from the heat dissipation of vertical cavity surface emitting lasers in the prior art, an embodiment of the present invention provides a vertical cavity surface emitting laser array with microchannels and a preparation method thereof. By setting microchannels between adjacent laser array units, the cooling medium can directly flow through the active area of ​​the laser and heat sources such as upper and lower Bragg reflectors (DBRs), so as to directly cool the VCSEL array, improve the heat dissipation efficiency, and facilitate the improvement of the working performance of the high-power VCSEL array.

[0007] (II) Technical solution

[0008] In view of the above technical problems, an embodiment of the present invention provides a vertical cavity surface emitting laser array with microchannels and a preparation method thereof.

[0009] According to a first aspect of the present invention, a vertical cavity surface emitting laser array with a microchannel is provided, comprising: a substrate having a first surface and a second surface arranged opposite to each other; a functional structure layer, located on the first surface of the substrate, comprising N vertical cavity surface emitting laser units and a microchannel; a cover layer, located on a side of the functional structure layer away from the substrate; a first electrode, located on the second surface, wherein the vertical cavity surface emitting laser unit is located on the first surface; N is a positive integer greater than or equal to 2, and the N vertical cavity surface emitting laser units are arranged in an array at a preset spacing to obtain a laser array with grooves; at least a portion of the microchannels are arranged inside the channel formed by the grooves and the cover layer.

[0010] In some exemplary embodiments, the VCSEL unit includes a VCSEL table and a second electrode, wherein at least a portion of the second electrode is located on a side of the VCSEL table away from the substrate; and a light exit hole of the VCSEL unit is located on a side of the VCSEL table away from the substrate.

[0011] In some exemplary embodiments, the functional structure layer further includes an anti-reflection film disposed between the light output hole and the cover layer.

[0012] In some exemplary embodiments, the functional structure layer further includes a passivation layer.

[0013] In some exemplary embodiments, the second electrode is located on a surface of the VCSEL table away from the substrate; and the passivation layer covers at least a portion of the side of the VCSEL unit facing the groove, at least a portion of the surface of the substrate facing the groove, and the side of the outermost VCSEL unit, wherein the passivation layer on the side of the outermost VCSEL unit is provided with an opening along a direction parallel to the groove, and the channel between the opening and the cover layer is a microchannel; and the channel between the passivation layer and the cover layer is a microchannel.

[0014] In some exemplary embodiments, the passivation layer covers at least a portion of the surface of the VCSEL mesa away from the substrate, at least a portion of the side of the VCSEL mesa facing the groove, at least a portion of the surface of the substrate facing the groove, and the side of the outermost VCSEL unit, wherein the passivation layer covering the side of the outermost VCSEL unit is provided with an opening along a direction parallel to the groove; the second electrode covers at least a portion of the surface of the passivation layer away from the substrate, at least a portion of the side of the passivation layer facing the groove or the opening, and at least a portion of the surface of the substrate facing the groove or the substrate, and at least a portion of the second electrode is located on a side surface of the VCSEL mesa away from the substrate, wherein the channel between the second electrode and the cover layer is a microchannel.

[0015] In some exemplary embodiments, the side surface of the microchannel includes at least one of a flat surface and a curved surface; and the microchannel includes at least one cooling medium inlet and a cooling medium outlet.

[0016] According to a second aspect of the present invention, a method for preparing a vertical cavity surface emitting laser array with a microchannel is provided, comprising: obtaining a vertical cavity surface emitting laser epitaxial wafer, the epitaxial wafer comprising a substrate and an epitaxial structure required for obtaining a vertical cavity surface emitting laser table; performing photolithography on the vertical cavity surface emitting laser epitaxial wafer to form a vertical cavity surface emitting laser table structure; preparing a passivation layer and a second electrode, wherein the vertical cavity surface emitting laser table and the second electrode constitute a vertical cavity surface emitting laser unit, and the vertical cavity surface emitting lasers are arranged in an array at a preset spacing to obtain a laser array with grooves; obtaining a cap layer material, and connecting the cap layer to the passivation layer by an ion bonding process; thinning, polishing and evaporating a metal material on the substrate to form a first electrode, wherein the groove and the cap layer form a microchannel structure.

[0017] In some exemplary embodiments, preparing the passivation layer and the second electrode includes: depositing the passivation layer material by a plasma enhanced chemical vapor deposition process so that the height of the passivation layer material is higher than the height of the vertical cavity surface emitting laser table; etching the passivation layer material by a semiconductor etching process to form a microchannel flow structure; and preparing the second electrode on the surface of the vertical cavity surface emitting laser table away from the substrate by a magnetron sputtering process or an electron beam evaporation process, wherein the sum of the heights of the second electrode and the vertical cavity surface emitting laser table is equal to the thickness of the deposited passivation layer material; the passivation layer covers at least a portion of the side surface of the vertical cavity surface emitting laser unit facing the groove, at least a portion of the surface of the substrate facing the groove, and the side surface of the outermost vertical cavity surface emitting laser unit; the passivation layer on the side surface of the outermost vertical cavity surface emitting laser unit is provided with an opening along a direction parallel to the groove, and the channel between the opening and the cover layer is a microchannel; and the channel between the passivation layer and the cover layer is a microchannel.

[0018] In some exemplary embodiments, preparing the passivation layer and the second electrode includes: depositing the passivation layer material by a plasma enhanced chemical vapor deposition process so that the height of the passivation layer material is equal to the height of the vertical cavity surface emitting laser table; etching the passivation layer material by a semiconductor etching process to form a microchannel flow structure; and preparing the second electrode by a magnetron sputtering process or an electron beam evaporation process, wherein the passivation layer covers at least a portion of the surface of the vertical cavity surface emitting laser table away from the substrate, at least a portion of the side of the vertical cavity surface emitting laser table facing the groove, at least a portion of the surface of the substrate facing the groove, and the side of the outermost vertical cavity surface emitting laser unit, wherein the passivation layer covering the side of the outermost vertical cavity surface emitting laser unit is provided with an opening in a direction parallel to the groove; the second electrode covers at least a portion of the surface of the passivation layer away from the substrate, at least a portion of the side of the passivation layer facing the groove or the opening, and at least a portion of the surface of the substrate facing the groove or the substrate, and at least a portion of the second electrode is located on the side surface of the vertical cavity surface emitting laser table away from the substrate; and the channel between the second electrode and the cap layer is a microchannel.

[0019] (III) Beneficial effects

[0020] It can be seen from the above technical solutions that the vertical cavity surface emitting laser array with microchannels and the preparation method thereof provided by the embodiments of the present invention have at least one of the following beneficial effects:

[0021] (1) By setting up microchannels between adjacent laser array units, the cooling medium can flow directly through the active area of ​​the laser and heat sources such as the upper and lower Bragg reflectors (DBRs) to directly cool the VCSEL array, greatly shortening the heat transfer path, thereby reducing the overall thermal resistance of the VCSEL array and improving the heat dissipation efficiency, which is beneficial to improving the working performance of the high-power VCSEL array.

[0022] (2) The microchannel is equipped with multiple inlets and outlets, so that the cooling medium flows through multiple flow channels in parallel, further improving the heat dissipation efficiency of the microchannel.

[0023] (3) The side of the microchannel is set to be wavy, thereby increasing the contact area between the side wall and the cooling medium and further increasing the heat dissipation efficiency. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1 The overall structural diagram of a vertical cavity surface emitting laser array with microchannels according to an embodiment of the present invention is schematically shown;

[0025] Figure 2 A schematic diagram of the structure of the functional structure layer of the first vertical cavity surface emitting laser with microchannel according to an embodiment of the present invention is shown;

[0026] Figure 3 The cross-sectional structure diagram of the first vertical cavity surface emitting laser with a microchannel according to an embodiment of the present invention is schematically shown;

[0027] Figure 4 A schematic diagram of the structure of the functional structure layer of a second vertical cavity surface emitting laser with a microchannel according to an embodiment of the present invention is shown;

[0028] Figure 5 A schematic diagram of the cross-sectional structure of a second vertical cavity surface emitting laser with a microchannel according to an embodiment of the present invention is shown;

[0029] Figure 6 A schematic diagram of a process of manufacturing a vertical cavity surface emitting laser array with microchannels according to an embodiment of the present invention is shown;

[0030] Figure 7 A schematic diagram schematically shows a process diagram of a first method for preparing a passivation layer and a second electrode according to an embodiment of the present invention; and

[0031] Figure 8 The flowchart of the second method for preparing the passivation layer and the second electrode according to an embodiment of the present invention is schematically shown.

[0032] Description of reference numerals:

[0033] 1-substrate; 2-first electrode; 3-functional structure layer; 31-vertical cavity surface emitting laser unit; 311-vertical cavity surface emitting laser table; 312-second electrode; 313-light output hole; 314-antireflection film; 32-passivation layer; 33-microchannel; 331-microchannel flow channel; 332-microchannel wall; 4-cover layer. DETAILED DESCRIPTION

[0034] In order to make the purpose, technical scheme and advantages of the present invention more clearly understood, the present invention is further described in detail below in combination with specific embodiments and with reference to the accompanying drawings. Obviously, the described embodiments are 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 creative work are within the scope of protection of the present invention.

[0035] Figure 1 The overall structural diagram of a vertical cavity surface emitting laser array with microchannels according to an embodiment of the present invention is schematically shown.

[0036] like Figure 1As shown, the first vertical cavity surface emitting laser according to an embodiment of the present invention includes: a substrate 1 having a first surface and a second surface arranged opposite to each other; a functional structure layer 3 located on the first surface of the substrate 1; a cover layer 4 located on the side of the functional structure layer 3 away from the substrate 1; and a first electrode 2 located on the second surface.

[0037] Figure 2 The structure diagram of the functional structure layer of the first vertical cavity surface emitting laser with microchannel according to the embodiment of the present invention is schematically shown.

[0038] Figure 3 The cross-sectional structure diagram of a first vertical cavity surface emitting laser with a microchannel according to an embodiment of the present invention is schematically shown.

[0039] like Figure 2 and Figure 3 As shown, the first functional structure layer 3 of a vertical cavity surface emitting laser with a microchannel 33 according to an embodiment of the present invention includes N vertical cavity surface emitting laser units 31 and a microchannel 33, wherein the vertical cavity surface emitting laser unit 31 is located on the first surface; N is a positive integer greater than or equal to 2, and the N vertical cavity surface emitting laser units 31 are arranged in an array at a preset spacing to obtain a laser array with grooves; at least a portion of the microchannel 33 is arranged inside the channel formed by the groove and the cover layer 4.

[0040] In some exemplary embodiments, the vertical cavity surface emitting laser unit 31 includes a vertical cavity surface emitting laser table 311 and a second electrode 312, wherein at least a portion of the second electrode 312 is located on a side of the vertical cavity surface emitting laser table 311 away from the substrate 1; and the light output hole 313 of the vertical cavity surface emitting laser unit 31 is located on a side of the vertical cavity surface emitting laser table 311 away from the substrate 1.

[0041] Preferably, the functional structure layer 3 further includes an anti-reflection film 314 disposed between the light exit hole 313 and the cover layer 4 .

[0042] In some exemplary embodiments, the functional structure layer 3 further includes a passivation layer 32. The second electrode 312 is located on a side surface of the vertical cavity surface emitting laser table 311 away from the substrate 1; and the passivation layer 32 covers at least a portion of the side surface of the vertical cavity surface emitting laser unit 31 facing the groove, at least a portion of the surface of the substrate 1 facing the groove, and the side surface of the outermost vertical cavity surface emitting laser unit 31, wherein the passivation layer 32 on the side surface of the outermost vertical cavity surface emitting laser unit 31 is provided with an opening in a direction parallel to the groove, and the channel between the opening and the cover layer 4 is a microchannel 33; and the channel between the passivation layer 32 and the cover layer 4 is a microchannel 33. Optionally, the side surface of the microchannel 33 includes at least one of a plane or a curved surface; the material of the passivation layer 32 includes silicon dioxide (SiO2) and the microchannel 33 includes at least one cooling medium inlet and cooling medium outlet.

[0043] For example, the first electrode 2 is an N-face electrode located below the substrate 1, tightly connected to the lower surface of the substrate 1, with a thickness of 200 nm, for electrical connection. The sidewalls of the microchannel 33 are composed of the sidewalls of the SiO2 passivation layer 32 and the side surfaces of the vertical cavity surface emitting laser unit 31, both of which are located above the substrate 1 and have the same height. The sidewalls of the outermost microchannel 33 are composed of the sidewalls of the SiO2 passivation layer 32, with a width of 20 μm for bonding with the cover layer 4. The microchannel flow channel 331 is located between the microchannel walls 332, with the same height as the microchannel walls 332, and a width of about 10 μm. The sum of the height of the vertical cavity surface emitting laser table 311 and the height of the second electrode 312 is equal to the height of the SiO2 passivation layer 32. The SiO2 passivation layer 32 is used for electrical insulation between the substrate 1 and the VCSEL table 311. The thickness of the SiO2 passivation layer 32 above the substrate 1 and the width of the side wall of the VCSEL table 311 are both about 200 nm. The second electrode 312 is a P-face electrode. The material of the P-face electrode includes metals such as Ti / Au, Ti / Pt / Au, etc., which are commonly used for the P-face ohmic contact of the VCSEL table to provide electrical connection. The circular light-emitting hole 313 is located on the inner side of the second electrode 312. The diameter of the light-emitting hole 313 is smaller than the diameter of the VCSEL table 311. It is not filled with material or is filled with an anti-reflection film 314. The laser generated by the VCSEL unit 31 is emitted into the free space through the light-emitting hole 313 without being absorbed by the metal.

[0044] The microchannel wall 332 and the cover layer 4 are tightly connected to form a microchannel flow channel 331. Inlets and outlets are provided on both sides, and the cooling medium flows in from the inlet, absorbs the heat generated by the VCSEL unit in the microchannel flow channel 331, and flows out from the outlet. Since there is electrical isolation between the microchannel flow channel 331 and the vertical cavity surface emitting laser array, deionized water can be used as the cooling medium. In addition, the cooling medium can also be selected as nitrogen, carbon dioxide, argon and other gases. Preferably, the cooling medium is an electrically insulating liquid with high electrical strength (for example, dielectric strength>25kV), such as fluorinated liquid, silicone oil, etc., so that even if the VCSEL array contacts the liquid, there will be no short circuit.

[0045] Figure 4 The structural diagram of the functional structure layer 3 of the second vertical cavity surface emitting laser with microchannel according to the embodiment of the present invention is schematically shown.

[0046] Figure 5 The cross-sectional structure diagram of a second vertical cavity surface emitting laser with a microchannel according to an embodiment of the present invention is schematically shown.

[0047] like Figure 4 and Figure 5 As shown in FIG. 1 , a second vertical cavity surface emitting laser having a microchannel 33 according to an embodiment of the present invention is Figure 2 and Figure 3 Compared with the first vertical cavity surface emitting laser with microchannel 33 shown in FIG. 1 , the main difference is the structure of the functional structure layer 3. On the one hand, the microchannel 33 of the embodiment of the present invention is provided with multiple inlets and outlets, and the cooling medium flows through multiple flow channels in parallel, further improving the heat dissipation efficiency of the microchannel 33. On the other hand, the second electrode 312 and the passivation layer 32 of the embodiment of the present invention are arranged differently. Figure 2 and Figure 3 There are differences.

[0048] In the embodiment of the present invention, the passivation layer 32 covers at least a portion of the surface of the VCSEL mesa 311 away from the substrate 1, at least a portion of the side of the VCSEL mesa 311 facing the groove, at least a portion of the surface of the substrate 1 facing the groove, and the side of the outermost VCSEL unit 31, wherein the passivation layer 32 covering the side of the outermost VCSEL unit 31 is provided with an opening along a direction parallel to the groove; the second electrode 312 covers at least a portion of the surface of the passivation layer 32 away from the substrate 1, at least a portion of the side of the passivation layer 32 facing the groove or the opening, and at least a portion of the surface of the substrate 1 facing the groove or the substrate 1, and at least a portion of the second electrode 312 is located on a side surface of the VCSEL mesa 311 away from the substrate 1, wherein the channel between the second electrode 312 and the cover layer 4 is a microchannel 33.

[0049] For example, the second electrode 312 is a P-surface electrode, which partially covers the outer surface of the SiO2 passivation layer 32, the microchannel wall 332 and the microchannel flow channel 331, and leaves a circular light exit hole 313. Preferably, the thickness of the second electrode 312 is 200nm. The upper surface of the microchannel wall 332 and the SiO2 passivation layer 32 not covered by the second electrode 312 is used to bond with the cover layer 44 to form a tight connection.

[0050] Figure 6 The flowchart of a method for preparing a vertical cavity surface emitting laser array with a microchannel 33 according to an embodiment of the present invention is schematically shown.

[0051] like Figure 6 As shown, a method for preparing a vertical cavity surface emitting laser array having a microchannel 33 according to an embodiment of the present invention includes steps S110-S150.

[0052] In step S110 , a vertical cavity surface emitting laser epitaxial wafer is obtained, where the epitaxial wafer includes a substrate 1 and an epitaxial structure required for obtaining a vertical cavity surface emitting laser mesa 311 .

[0053] In step S120 , the VCSEL epitaxial wafer is photolithographically processed to form a VCSEL mesa 311 structure.

[0054] In step S130, a passivation layer 32 and a second electrode 312 are prepared, wherein the VCSEL table 311 and the second electrode 312 constitute a VCSEL unit 31, and the VCSELs are arranged in an array at a preset pitch to obtain a laser array with grooves.

[0055] In some exemplary embodiments, step S130 includes steps S210-S230, see Figure 7 , used to prepare Figure 2 and Figure 3 A first VCSEL array having a microchannel 33 is shown.

[0056] In step S210 , a plasma enhanced chemical vapor deposition process is used to deposit the material of the passivation layer 32 , so that the height of the passivation layer 32 material is higher than the height of the VCSEL mesa 311 .

[0057] In step S220, the passivation layer 32 material is etched using a semiconductor etching process to form a microchannel flow channel 331 structure. The oxidation limiting aperture of the VCSEL is formed by a selective wet process.

[0058] In step S230 , a second electrode 312 is prepared on a surface of the VCSEL mesa 311 away from the substrate 1 by using a magnetron sputtering process or an electron beam evaporation process.

[0059] In the implementation of the present invention, the sum of the heights of the second electrode 312 and the vertical cavity surface emitting laser table 311 is equal to the thickness of the deposited passivation layer 32 material; the passivation layer 32 covers at least a portion of the side surface of the vertical cavity surface emitting laser unit 31 facing the groove, at least a portion of the surface of the substrate 1 facing the groove, and the side surface of the outermost vertical cavity surface emitting laser unit 31; the passivation layer 32 on the side surface of the outermost vertical cavity surface emitting laser unit 31 is provided with an opening along a direction parallel to the groove, and the channel between the opening and the cover layer 4 is a microchannel 33; and the channel between the passivation layer 32 and the cover layer 4 is a microchannel 33.

[0060] For example, a SiO2 film is deposited by a plasma enhanced chemical vapor deposition (PECVD) method, and the film thickness is higher than the height of the VCSEL table. The SiO2 film is etched by a semiconductor etching (RIE) process to form a microchannel flow channel 331 structure. A P-surface electrode is prepared on the upper surface of the VCSEL table by a magnetron sputtering process or an electron beam evaporation process, and the sum of the electrode thickness and the VCSEL table height is equal to the thickness of the deposited SiO2 film.

[0061] In some exemplary embodiments, step S130 includes steps S310-S330, see Figure 8 , used to prepare Figure 4 and Figure 5 A second VCSEL array having a microchannel 33 is shown.

[0062] In step S310 , a plasma enhanced chemical vapor deposition process is used to deposit the material of the passivation layer 32 , so that the height of the passivation layer 32 material is equal to the height of the VCSEL mesa 311 .

[0063] In step S320 , the passivation layer 32 material is etched using a semiconductor etching process to form a microchannel flow channel 331 structure.

[0064] In step S330 , the second electrode 312 is prepared by a magnetron sputtering process or an electron beam evaporation process.

[0065] In the embodiment of the present invention, the passivation layer 32 covers at least a portion of the surface of the VCSEL table 311 away from the substrate 1, at least a portion of the side of the VCSEL table 311 facing the groove, at least a portion of the surface of the substrate 1 facing the groove, and the side of the outermost VCSEL unit 31, wherein the passivation layer 32 covering the side of the outermost VCSEL unit 31 is provided with an opening along a direction parallel to the groove; the second electrode 312 covers at least a portion of the surface of the passivation layer 32 away from the substrate 1, at least a portion of the side of the passivation layer 32 facing the groove or the opening, and at least a portion of the surface of the substrate 1 facing the groove or the substrate 1, and at least a portion of the second electrode 312 is located on the side surface of the VCSEL table 311 away from the substrate 1; and the channel between the second electrode 312 and the cover layer 4 is a microchannel 33.

[0066] For example, a SiO2 film is deposited by plasma enhanced chemical vapor deposition (PECVD) method, and the film thickness is the same as the height of the VCSEL table. The SiO2 film is etched by semiconductor etching (RIE) process to form a microchannel flow channel 331 structure. A P-side electrode is prepared on the surface of the SiO2 film by magnetron sputtering process or electron beam evaporation process, and the electrode thickness is 200nm.

[0067] In step S140 , the material of the cover layer 4 is obtained, and the cover layer 4 is connected to the passivation layer 32 by using an ion bonding process, wherein the groove and the cover layer 4 form a microchannel 33 structure.

[0068] For example, the cover layer 4 material includes a polydimethylsiloxane (PDMS) film, and a microchannel 33 structure is processed on the PDMS film using a laser etching or wet etching process, and the width of the microchannel 33 is about 10 μm and the height is about 10 μm; the prepared PDMS film microchannel 33 and the SiO2 layer on the surface of the VCSEL array are tightly connected by plasma bonding and other methods. After bonding, the projection of the microchannel flow channel 331 of the PDMS on the substrate 1 side coincides with the microchannel flow channel 331 on the substrate 1 side. Preferably, the etching depth of the microchannel flow channel 331 of the PDMS film is 10 μm.

[0069] In step S150 , the substrate 1 is thinned, polished, and subjected to metal vapor deposition to form a first electrode 2 .

[0070] The above specific embodiments further illustrate the purpose, technical solutions and beneficial effects of the present invention in detail. It should be understood that the above are only specific embodiments of the present invention and are 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 protection scope of the present invention.

Claims

1. A vertical cavity surface emitting laser array with microchannels, characterized in that: include: A substrate having a first surface and a second surface disposed opposite to each other; A functional structure layer, located on the first surface of the substrate, comprising N vertical cavity surface emitting laser units and a microchannel; A cover layer, located on a side of the functional structure layer away from the substrate; as well as a first electrode, located on the second surface, Wherein, the vertical cavity surface emitting laser unit is located on the first surface; N is a positive integer greater than or equal to 2, and the N vertical cavity surface emitting laser units are arranged in an array at a preset pitch to obtain a laser array with grooves; At least a portion of the microchannel is disposed inside a channel formed by the groove and the cover layer.

2. The vertical cavity surface emitting laser array with microchannels according to claim 1, characterized in that: The vertical cavity surface emitting laser unit comprises a vertical cavity surface emitting laser table and a second electrode, Wherein, at least a portion of the second electrode is located on a side of the VCSEL mesa away from the substrate; and The light exit hole of the VCSEL unit is located at a side of the VCSEL table away from the substrate.

3. The vertical cavity surface emitting laser array with microchannels according to claim 2, characterized in that: The functional structure layer further comprises an anti-reflection film, which is arranged between the light exit hole and the cover layer.

4. The vertical cavity surface emitting laser array with microchannels according to claim 2, characterized in that: The functional structure layer further includes a passivation layer.

5. The vertical cavity surface emitting laser array with microchannels according to claim 4, characterized in that: The second electrode is located on a side surface of the vertical cavity surface emitting laser table away from the substrate; as well as The passivation layer covers at least a portion of the side surface of the VCSEL unit facing the groove, at least a portion of the surface of the substrate facing the groove, and the side surface of the outermost VCSEL unit. Wherein, the passivation layer on the side of the outermost vertical cavity surface emitting laser unit is provided with an opening along a direction parallel to the groove, and the channel between the opening and the cover layer is the microchannel; as well as The channel between the passivation layer and the cover layer is the microchannel.

6. The vertical cavity surface emitting laser array with microchannels according to claim 4, characterized in that: The passivation layer covers at least a portion of the surface of the VCSEL mesa away from the substrate, at least a portion of the side surface of the VCSEL mesa facing the groove, at least a portion of the surface of the substrate facing the groove, and the side surface of the outermost VCSEL unit, wherein the passivation layer covering the side surface of the outermost VCSEL unit is provided with an opening along a direction parallel to the groove; The second electrode covers at least a portion of the surface of the passivation layer away from the substrate, at least a portion of the side of the passivation layer facing the groove or the opening, and at least a portion of the surface of the substrate facing the groove or the substrate, and at least a portion of the second electrode is located on a side surface of the vertical cavity surface emitting laser mesa away from the substrate, Wherein, the channel between the second electrode and the cover layer is the microchannel.

7. The vertical cavity surface emitting laser array with microchannels according to any one of claims 1 to 6, characterized in that: The microchannel side comprises at least one of a flat surface or a curved surface; and The microchannel includes at least one cooling medium inlet and one cooling medium outlet.

8. A method for preparing a vertical cavity surface emitting laser array with microchannels, characterized in that: include: Obtaining a vertical cavity surface emitting laser epitaxial wafer, wherein the epitaxial wafer includes a substrate and an epitaxial structure required for obtaining a vertical cavity surface emitting laser table; Performing photolithography on the vertical cavity surface emitting laser epitaxial wafer to form a vertical cavity surface emitting laser mesa structure; Prepare a passivation layer and a second electrode, wherein the VCSEL table and the second electrode constitute a VCSEL unit, and the VCSELs are arranged in an array at a preset pitch to obtain a laser array with grooves; Obtaining a cover layer material, and connecting the cover layer to the passivation layer using an ion bonding process; and The substrate is thinned, polished and evaporated with metal material to form a first electrode. Wherein, the groove and the cover layer form a microchannel structure.

9. The method according to claim 8, characterized in that The preparation of the passivation layer and the second electrode comprises: The passivation layer material is deposited by plasma enhanced chemical vapor deposition process, so that the height of the passivation layer material is higher than the height of the vertical cavity surface emitting laser table Etching the passivation layer material using a semiconductor etching process to form a microchannel flow structure; and A second electrode is prepared on a surface of the vertical cavity surface emitting laser table away from the substrate by using a magnetron sputtering process or an electron beam evaporation process, wherein the sum of the heights of the second electrode and the vertical cavity surface emitting laser table is equal to the thickness of the deposited passivation layer material; The passivation layer covers at least a portion of the side surface of the VCSEL unit facing the groove, at least a portion of the surface of the substrate facing the groove, and the side surface of the outermost VCSEL unit; The passivation layer on the side of the outermost VCSEL unit is provided with an opening in a direction parallel to the groove, and the channel between the opening and the cover layer is the microchannel; and The channel between the passivation layer and the cover layer is the microchannel.

10. The method according to claim 8, characterized in that The preparation of the passivation layer and the second electrode comprises: Depositing the passivation layer material by plasma enhanced chemical vapor deposition process so that the height of the passivation layer material is equal to the height of the vertical cavity surface emitting laser table; Etching the passivation layer material using a semiconductor etching process to form a microchannel flow structure; and The second electrode is prepared by magnetron sputtering or electron beam evaporation. The passivation layer covers at least a portion of a surface of the VCSEL mesa away from the substrate, at least a portion of a side surface of the VCSEL mesa facing the groove, at least a portion of a surface of the substrate facing the groove, and a side surface of an outermost VCSEL unit, wherein the passivation layer covering the side surface of the outermost VCSEL unit is provided with an opening along a direction parallel to the groove; The second electrode covers at least a portion of a surface of the passivation layer away from the substrate, at least a portion of a side surface of the passivation layer facing the groove or the opening, and at least a portion of a surface of the substrate facing the groove or the substrate, and at least a portion of the second electrode is located on a side surface of the VCSEL mesa away from the substrate; and The channel between the second electrode and the cover layer is the microchannel.

Images