阅读说明：本技术 晶圆级vcsel激光阵列结构及制备方法 (Wafer-level VCSEL laser array structure and preparation method thereof ) 是由 王智勇 兰天 李冲 李颖 代京京 于 2020-12-25 设计创作，主要内容包括：本发明公开了晶圆级VCSEL激光阵列结构及制备方法,属于激光器技术领域,包括晶圆级VCSEL激光芯片,晶圆级VCSEL激光芯片从下至上依次包括衬底层、缓冲层、第一反射镜、氧化层、有源层、第二反射镜以及盖层；在缓冲层上刻蚀形成发光单元阵列,且发光单元电连接；位于衬底层上的第三反射镜；位于第三反射镜上的多个相位差补偿膜；每个相位差补偿膜与发光单元阵列中相邻两个发光单元之间中心处位于同一条直线上。本发明采用一体化集成,直接将整片晶圆级VCSEL激光芯片制备成发光单元阵列,实现晶圆级VCSEL激光芯片的最大利用化,同时使得发光单元阵列满足实现Talbot效应,最终在衬底层获得同相位相干输出的VCSEL激光。(The invention discloses a wafer-level VCSEL laser array structure and a preparation method thereof, belonging to the technical field of lasers and comprising a wafer-level VCSEL laser chip, wherein the wafer-level VCSEL laser chip sequentially comprises a substrate layer, a buffer layer, a first reflector, an oxide layer, an active layer, a second reflector and a cover layer from bottom to top; etching the buffer layer to form a light-emitting unit array, wherein the light-emitting units are electrically connected; a third mirror on the substrate layer; a plurality of retardation compensation films on the third mirror; the center between each phase difference compensation film and two adjacent light-emitting units in the light-emitting unit array is positioned on the same straight line. The invention adopts integrated integration, directly prepares the whole wafer level VCSEL laser chip into the light emitting unit array, realizes the maximum utilization of the wafer level VCSEL laser chip, simultaneously enables the light emitting unit array to meet the requirement of realizing the Talbot effect, and finally obtains the VCSEL laser of same-phase coherent output on the substrate layer.)

1. A wafer-level VCSEL laser array structure, comprising:

the wafer-level VCSEL laser chip comprises a substrate layer, a buffer layer, a first reflector, an oxide layer, an active layer, a second reflector and a cover layer from bottom to top in sequence;

etching the buffer layer to form a light emitting unit array, wherein the light emitting units are electrically connected;

a third mirror at the bottom of the substrate layer; and

a plurality of retardation compensation films on the bottom of the third mirror;

wherein, the center between each phase difference compensation film and two adjacent light-emitting units in the light-emitting unit array is positioned on the same straight line.

2. The wafer-level VCSEL laser array structure of claim 1, wherein the reflectance R1 of the first mirror < the reflectance R3 of the third mirror < the reflectance R2 of the second mirror such that light emitted by the light emitting unit is emitted from the substrate layer.

3. The wafer level VCSEL laser array structure of claim 1, wherein the substrate layer is electrically non-conductive and an optical window is disposed in the oxide layer.

4. The wafer-level VCSEL laser array structure of claim 1, wherein the light emitting cell array electrical connections comprise parallel connections or series connections;

the buffer layers between the adjacent light-emitting units are connected in parallel, a second electrode contact layer is arranged on the buffer layer, and a passivation layer is arranged on the second electrode contact layer; a first electrode contact layer is arranged on the wafer-level VCSEL laser chip, so that the first electrode contact layer covers the light emitting unit array and the passivation layer, and the light emitting units are connected in parallel;

and the second electrode contact layer, the passivation layer and one side and the top layer of the light-emitting unit which are contacted with the passivation layer are provided with the first electrode contact layer, so that the light-emitting units are connected in series.

5. The wafer-level VCSEL laser array structure of claim 4, wherein an annular electrode contact region contacting the buffer layer is disposed at an edge of the wafer-level VCSEL laser chip, an isolation trench contacting the substrate layer is disposed at a symmetrical position of the annular electrode contact region, and the isolation trench divides the annular electrode contact region into a first electrode contact region and a second electrode contact region, so that a positive current of an external circuit flows into the light emitting cell array through the first electrode contact region and is connected to a negative electrode of the external circuit from the second electrode contact region.

6. The wafer-level VCSEL laser array structure of claim 1, wherein the light emitting cell array is periodically arranged to achieve Talbot effect, wherein the Talbot distance L is:

wherein λ is a light emission wavelength of the light emitting unit; n is the refractive index of the light-transmitting medium; d₀The distance between the centers of two adjacent light-emitting units is disclosed.

7. The wafer level VCSEL laser array structure of claim 6, wherein the thickness D of the substrate layer is based on fractional Talbot effect₀Comprises the following steps:

D₀＝L/N

wherein N is a natural number.

8. The wafer-level VCSEL laser array structure of claim 1, wherein the length and width of the phase difference compensation film is ≦ a pitch of the adjacent light emitting cells.

9. The wafer-level VCSEL laser array structure of claim 1, wherein the phase of the phase difference compensation film is:

wherein N is 0,1,2, ….

10. The method of fabricating a wafer level VCSEL laser array structure of any of claims 1-9, comprising:

providing a wafer-level laser epitaxial wafer, wherein the wafer-level laser epitaxial wafer sequentially comprises a substrate layer, a buffer layer, a first reflector, an oxide layer, an active layer, a second reflector and a cover layer from bottom to top;

photoetching the wafer-level laser epitaxial wafer to form a light-emitting unit array on the buffer layer, wherein the light-emitting units are arranged periodically to meet the Talbot effect;

preparing a first electrode contact layer and a second electrode contact layer by adopting a mask and sputtering process to form the light-emitting units connected in parallel;

etching the edge of the wafer-level laser epitaxial wafer within the range of 1-10 mm to the buffer layer by adopting a mask and etching process to form an annular contact region, etching the two symmetrical ends of the annular contact region to the substrate layer by adopting a deep etching technology to form an isolation channel, and dividing the annular contact region into a first electrode contact region and a second electrode contact region;

connecting the first electrode contact area with the first electrode contact layer and connecting the second electrode contact area with the second electrode contact layer through a metal sputtering process to form a light-emitting unit array with a parallel structure;

meanwhile, on the basis, the light emitting unit array with the parallel structure is prepared into a light emitting unit array with a serial structure by using the mask, etching, deposition and sputtering processes again;

grinding, thinning and polishing processes are utilized to enable the thickness of the substrate layer to be D₀To satisfy the fractional Talbot effect;

arranging a third reflector on the substrate layer in a vacuum coating mode;

and evaporating a phase difference compensation film on the surface of the third reflector.

Technical Field

The invention relates to the technical field of lasers, in particular to a wafer-level VCSEL laser array structure and a preparation method thereof.

Background

The Vertical Cavity Surface Emitting Laser (VCSEL) has the excellent structural characteristics and physical characteristics of small volume, light emitting direction perpendicular to a substrate, easiness in two-dimensional integration, small threshold current, circularly symmetric light spots, single longitudinal mode working, high modulation rate and the like, and has obvious advantages in the aspects of accuracy, miniaturization, compactness, low power consumption, reliability and the like compared with an Edge Emitting Laser (EEL). Since birth, the VCSEL is used as a core device for a new generation of optical storage and optical communication applications, and is applied to the fields of optical parallel processing, optical identification, optical interconnection systems, optical storage and the like. With the improvement of processes and material technologies, the advantages of VCSEL devices in the fields of power consumption, manufacturing cost, integration, heat dissipation, etc. begin to emerge, and VCSEL devices are gradually applied to commercial-grade applications such as industrial heating, environmental monitoring, medical devices, etc. and consumer-grade applications such as 3D sensing, etc. In the future, with the continuous development of the intelligent information world, the VCSEL is widely applied to the fields of consumer electronics 3D imaging, internet of things, data center/cloud computing, automatic driving and the like. Wherein, VCSEL plays more and more important effect in consumer electronics field, and VCSEL can be used to carry out smart mobile phone face identification, unmanned aerial vehicle keeps away barrier, VR/AR, sweep floor robot, domestic camera etc..

With the continuous advance and development of technology, each application field has higher application requirements on the device performance of the VCSEL laser, and especially, higher requirements on the output power and the beam quality of the VCSEL laser are put forward, that is, a VCSEL array laser with high brightness needs to be obtained. Therefore, in order to further increase the output power, VCSEL array lasers are thus produced. However, due to the limitation of the manufacturing process, the lasing wavelength of each VCSEL light emitting unit in the VCSEL array laser is difficult to be completely consistent, so that coherent output among the light emitting units cannot be realized, and thus the quality of laser beams output by the VCSEL array laser is generally poor. In addition, the VCSEL array laser has a small size, and the VCSEL array laser generates a large amount of heat, so that the high-power VCSEL array laser also faces a problem of efficient heat dissipation. In addition, in order to obtain a larger power output, the area of the VCSEL array laser array and the number of light emitting units are generally increased, and the required current is also increased, so that the power supply source also becomes a problem of limiting the output power of the laser.

Disclosure of Invention

Aiming at the defects existing in the problems, the invention provides a wafer-level VCSEL laser array structure and a preparation method thereof.

To achieve the above object, the present invention provides a wafer level VCSEL laser array structure, comprising:

the wafer-level VCSEL laser chip comprises a substrate layer, a buffer layer, a first reflector, an oxide layer, an active layer, a second reflector and a cover layer from bottom to top in sequence;

etching the buffer layer to form a light-emitting unit array, wherein the light-emitting units are electrically connected;

a third mirror at the bottom of the substrate layer; and

a plurality of retardation compensation films on the bottom of the third mirror;

wherein, the center between each phase difference compensation film and two adjacent light-emitting units in the light-emitting unit array is positioned on the same straight line.

Preferably, the reflectance R1 of the first mirror < the reflectance R3 of the third mirror < the reflectance R2 of the second mirror is such that light emitted by the light emitting unit is emitted from the substrate layer.

Preferably, the substrate layer is electrically non-conductive and the oxide layer has an optical window therein.

Preferably, the light emitting cell array electrical connection includes a parallel connection or a series connection;

the buffer layers between the adjacent light-emitting units are connected in parallel, a second electrode contact layer is arranged on the buffer layer, and a passivation layer is arranged on the second electrode contact layer; a first electrode contact layer is arranged on the wafer-level VCSEL laser chip, so that the first electrode contact layer covers the light emitting unit array and the passivation layer, and the light emitting units are connected in parallel;

and the second electrode contact layer, the passivation layer and one side and the top layer of the light emitting unit which is in contact with the passivation layer are provided with the first electrode contact layer, so that the light emitting units are connected in series.

Preferably, the edge of the wafer-level VCSEL laser chip is provided with an annular electrode contact area which is in contact with the buffer layer, the symmetrical position of the annular contact area is provided with an isolation channel which is in contact with the substrate layer, and the isolation channel divides the annular contact area into a first electrode contact area and a second electrode contact area, so that the positive current of an external circuit flows into the light-emitting unit array through the first electrode contact area and is accessed to the negative electrode of the external circuit from the second electrode contact area.

Preferably, the light emitting unit array adopts a periodic arrangement mode to realize a Talbot effect, and the Talbot distance L is:

wherein λ is a light emission wavelength of the light emitting unit; n is the refractive index of the light-transmitting medium; d₀The distance between the centers of two adjacent light-emitting units is disclosed.

Preferably, the thickness D of the substrate layer is based on the fractional Talbot effect₀Comprises the following steps:

D₀＝L/N

wherein N is a natural number.

Preferably, the length and width of the phase difference compensation film are ≦ the pitch of the adjacent light emitting cells.

Preferably, the phase of the phase difference compensation film is:

wherein N is 0,1,2, ….

The invention also provides a preparation method of the wafer-level VCSEL laser array structure, which comprises the following steps:

providing a wafer-level laser epitaxial wafer, wherein the wafer-level laser epitaxial wafer sequentially comprises a substrate layer, a buffer layer, a first reflector, an oxide layer, an active layer, a second reflector and a cover layer from bottom to top;

photoetching the wafer-level laser epitaxial wafer to form a light-emitting unit array on the buffer layer, wherein the light-emitting units are arranged periodically to meet the Talbot effect;

preparing a first electrode contact layer and a second electrode contact layer by adopting a mask and sputtering process to form the light-emitting units connected in parallel;

etching the edge of the wafer-level laser epitaxial wafer within the range of 1-10 mm to the buffer layer by adopting a mask and etching process to form an annular contact region, etching the two symmetrical ends of the annular contact region to the substrate layer by adopting a deep etching technology to form an isolation channel, and dividing the annular contact region into a first electrode contact region and a second electrode contact region;

connecting the first electrode contact area with the first electrode contact layer and connecting the second electrode contact area with the second electrode contact layer through a metal sputtering process to form a light-emitting unit array with a parallel structure;

meanwhile, on the basis, the light emitting unit array with the parallel structure is prepared into a light emitting unit array with a serial structure by using the mask, etching, deposition and sputtering processes again;

grinding, thinning and polishing processes are utilized to enable the thickness of the substrate layer to be D₀To satisfy the fractional Talbot effect;

arranging a third reflector on the substrate layer in a vacuum coating mode;

and evaporating a phase difference compensation film on the surface of the third reflector.

Compared with the prior art, the invention has the beneficial effects that:

the invention adopts integrated integration, directly prepares the whole wafer level VCSEL laser chip into the light emitting unit array, realizes the maximum utilization of the wafer level VCSEL laser chip, simultaneously enables the light emitting unit array to meet the requirement of realizing the Talbot effect, and finally obtains the VCSEL laser of same-phase coherent output on the substrate layer.

Drawings

FIG. 1 is a schematic cross-sectional view of a wafer level VCSEL laser chip according to the present invention;

FIG. 2 is a schematic view of a structure in which light emitting cells are connected in parallel according to the present invention;

FIG. 3 is a schematic view of a structure in which light emitting cells are connected in series according to the present invention;

FIG. 4 is a top view of the annular electrode contact region of the present invention;

FIG. 5 is a schematic structural diagram of a light emitting unit array according to the present invention for realizing the Talbot effect;

FIG. 6 is a top view of a periodic array of three light-emitting units according to the present invention.

Reference numerals:

1A, 1B, 1C, a light emitting unit; 101. a substrate layer; 102. a buffer layer; 103. a first reflector; 104. an active layer; 105. an oxide layer; 106. a second mirror layer; 107: a cap layer; 108. a first electrode contact layer; 109. a second electrode contact layer; 110. a passivation layer; 111. a first VCSEL laser beam; 112. a second VCSEL laser beam; 113. a third reflector; 114: a phase difference compensation film; 115: an optical window; 116: an insulating trench layer; 117: a first electrode contact region; 118: a second electrode contact region; 119: isolating the channel.

Detailed Description

In order to make the objects, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are some, but not all, embodiments of the present invention. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

In the description of the present invention, it should be noted that the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", and the like indicate orientations or positional relationships based on the orientations or positional relationships shown in the drawings, and are only for convenience of description and simplicity of description, but do not indicate or imply that the device or element being referred to must have a specific orientation, be constructed and operated in a specific orientation, and thus, should not be construed as limiting the present invention. Furthermore, the terms "first," "second," and "third" are used for descriptive purposes only and are not to be construed as indicating or implying relative importance.

In the description of the present invention, it should also be noted that, unless otherwise explicitly specified or limited, the terms "mounted," "connected," and "connected" are to be construed broadly, e.g., as meaning either a fixed connection, a removable connection, or an integral connection; can be mechanically or electrically connected; they may be connected directly or indirectly through intervening media, or they may be connected internally or indirectly. The specific meaning of the above terms in the present invention can be understood in specific cases to those skilled in the art.

The invention is described in further detail below with reference to the accompanying figures 1-6:

referring to fig. 1, the present invention provides a wafer level VCSEL laser array structure, comprising:

the wafer-level VCSEL laser chip sequentially comprises a substrate layer 101, a buffer layer 102, a first reflector 103, an oxide layer 105, an active layer 104, a second reflector 106 and a cover layer 107 from bottom to top;

specifically, wafer-level VCSEL laser chip sizes include 2 inches, 3 inches, 4 inches, 6 inches, 8 inches, and so on; the substrate layer 101 is non-conductive, using non-conductive materials such as undoped GaAs, Si, SiC, etc. An optical window 115 is arranged in the oxide layer 105 and used for a VCSEL laser emitting window; the first mirror 103 and the second mirror 106 can be selected from bragg mirrors or high-contrast gratings, and the reflectivity R1 of the first mirror 103 is 60% -99%, the reflectivity R2 of the second mirror 106 is 90% -99.9%, and the reflectivity R1 of the first mirror 103 is less than the reflectivity R2 of the second mirror 106.

Etching the buffer layer 102 to form a light emitting unit array, wherein the light emitting units are electrically connected;

in particular, the light emitting unit is suitable for any semiconductor material system, such as GaAs, GaN, InP, etc., and is also suitable for any light emitting band, such as ultraviolet band, blue/green light, red light band, infrared band, etc.

A third mirror 113 located at the bottom of the substrate layer 101;

specifically, the reflectance R1 of the first mirror 103 < the reflectance R3 of the third mirror 113 < the reflectance R2 of the second mirror 106 causes light emitted from the light emitting unit to be emitted from the substrate layer 101.

A plurality of phase difference compensation films 114 located at the bottom of the third mirror 113;

wherein, each phase difference compensation film 114 is located on the same straight line with the center between two adjacent light emitting units in the light emitting unit array.

Specifically, ZrO/SiO is used as the retardation compensation film 114₂And the compensated phase difference of the multilayer dielectric materials is as follows:

wherein N is 0,1,2, ….

In this embodiment, the light emitting cells are electrically connected in parallel or in series,

as shown in fig. 2, which is an array structure of light emitting cells connected in parallel, a second electrode contact layer 109 is disposed on the buffer layer 102 between adjacent light emitting cells, and a passivation layer 110 is disposed on the second electrode contact layer 109; a first electrode contact layer 108 is arranged on the wafer-level VCSEL laser chip, so that the first electrode contact layer 108 covers the light emitting unit array and the passivation layer 110, and the light emitting units are connected in parallel;

as shown in fig. 3, in the light emitting cell array structure connected in series, an insulating communication layer 116 contacting the substrate is disposed at the center of adjacent light emitting cells, a second electrode contact layer 109 is disposed between the insulating communication layer 116 and one light emitting cell, a passivation layer 110 is disposed between the other light emitting cell, and a first electrode contact layer 108 is disposed at one side and a top layer of the second electrode contact layer 109, the passivation layer 110, and the light emitting cell contacting the passivation layer 110, so that the light emitting cells are connected in series.

Referring to fig. 4, an annular electrode contact region contacting the buffer layer 102 is disposed at an edge of the wafer-level VCSEL laser chip, an isolation trench 119 contacting the substrate layer 101 is disposed at a symmetrical position of the annular electrode contact region, and the isolation trench 119 divides the annular electrode contact region into a first electrode contact region 117 and a second electrode contact region 118, so that an external circuit positive electrode current flows into the light emitting cell array through the first electrode contact region 117 and is connected to an external circuit negative electrode from the second electrode contact region 118.

Specifically, the parallel connection current flow direction is:

after the current of the positive electrode of the external circuit passes through the first electrode contact area 117 and enters the first electrode contact layer 108, the current is simultaneously injected into the light-emitting units, sequentially passes through the cover layer 107, the second reflector 106, the active layer 104, the oxide layer 105, the first reflector 103 and the buffer layer 102, and then is connected into the negative electrode of the external circuit from the second electrode contact area 118 through the second electrode contact layer 109, namely the light-emitting units are connected in parallel;

the series connection current flow direction is:

the positive current of the external circuit flows into a first electrode contact layer 108 through a first electrode contact area 117, then is injected into the light-emitting units contacted with the first electrode contact layer 108, sequentially passes through the cover layer 107, the second reflector 106, the active layer 104, the oxide layer 105, the first reflector 103 and the buffer layer 102, then passes through the second electrode contact layer 109, flows into the next first electrode contact layer 108, then enters the adjacent light-emitting units, sequentially flows into each light-emitting unit until the negative electrode of the external circuit is accessed from the last second electrode contact area 118, and namely the light-emitting units are connected in series.

Referring to fig. 5, the light emitting unit array adopts a periodic arrangement mode to realize the Talbot effect, and the Talbot distance L is:

wherein λ is a light emission wavelength of the light emitting unit; n is the refractive index of the light-transmitting medium; d₀Is the distance between the centers of two adjacent light-emitting units.

Further, the thickness D of the substrate layer 101 is based on the fractional Talbot effect₀Comprises the following steps:

D₀＝L/N

wherein N is a natural number. I.e. the thickness D of the substrate layer 101₀May be L, L/2, L/4, etc.

Still further, the phase of the phase difference compensation film 114 is:

wherein N is 0,1,2, ….

And the length and width of the retardation compensation film 114 are not more than the pitch of the adjacent light emitting cells.

Referring to fig. 6, three periodically distributed light emitting cell array structures capable of generating the Talbot effect are shown, namely, a square distribution (6A), a diamond distribution (6B) and a regular hexagonal distribution (6C).

In the present embodiment, with the above-described structure, the VCSEL laser beam having a certain divergence angle θ is emitted from the substrate layer 101, that is, the first VCSEL laser beam 111 perpendicular to the substrate layer 101 is emitted from the VCSEL light-emitting unit 1A, and the second VCSEL laser beam 112 obliquely incident on the substrate layer 101 at the outermost side is simplified. Due to the Talbot effect, there is a phase difference between the first VCSEL laser beam 111 and the second VCSEL laser beam 112. Therefore, after passing through the phase difference compensation film 114, the phase difference between the first VCSEL laser beam 111 and the second VCSEL laser beam 112 can be compensated, and finally the VCSEL laser beam 115 with the same phase and coherence is emitted from the back surface of the substrate layer 101, and the VCSEL laser beam 115 has ultra-high brightness.

The invention also provides a preparation method of the wafer-level VCSEL laser array structure, which comprises the following steps:

providing a wafer-level laser epitaxial wafer, wherein the wafer-level laser epitaxial wafer sequentially comprises a substrate layer 101, a buffer layer 102, a first reflector 103, an oxide layer 105, an active layer 104, a second reflector 106 and a cover layer 107 from bottom to top;

photoetching is carried out on the wafer-level laser epitaxial wafer, so that a light-emitting unit array is formed on the buffer layer 102, and the light-emitting units are arranged periodically to meet the Talbot effect;

preparing a first electrode contact layer 108 and a second electrode contact layer 109 by adopting a mask and sputtering process to form light-emitting units connected in parallel;

etching the edge of the wafer-level laser epitaxial wafer within the range of 1-10 mm to the buffer layer 102 by using a mask and etching process to form an annular contact region, etching the two symmetrical ends of the annular contact region to the substrate layer 101 by using a deep etching technology to form an isolation channel 119, and dividing the annular contact region into a first electrode contact region 117 and a second electrode contact region 118;

connecting the first electrode contact region 117 with the first electrode contact layer 108 and connecting the second electrode contact region 118 with the second electrode contact layer 109 through a sputtering metal process to form a light emitting unit array with a parallel structure;

meanwhile, on the basis, the light emitting unit array with the parallel structure is prepared into a light emitting unit array with a serial structure by using the mask, etching, deposition and sputtering processes again;

the thickness of the substrate layer 101 is D by grinding, thinning and polishing processes₀To satisfy the fractional Talbot effect;

a third reflector 113 is arranged on the substrate layer 101 in a vacuum coating mode;

a retardation compensation film 114 is deposited on the surface of the third mirror 113.

The invention also provides a concrete example of the GaAs-based VCSEL laser chip wafer, which comprises the following concrete steps:

the VCSEL laser chip comprises a GaAs substrate layer 101, an n-type GaAs buffer layer 102, an n-type AlAs/GaAs first reflecting mirror 103 and Al from bottom to top₉₀A GaAs oxide layer 105, an InGaAs/GaAsP active layer 104, a p-type AlAs/GaAs second mirror 106, a p-type GaAs cap layer 107, and an output wavelength λ of 940 nm;

wherein the GaAs wafer size is 2 inches, and the n-type doping source is Si₂H₆The doping concentration is 2e18/cm³～1e19/cm³The p-type doping source is Si₂H₆The doping concentration is 5e18/cm³～1e20/cm³；

The n-type AlAs/GaAs first mirror 103 has a reflectivity R1 of 86% and the p-type AlAs/GaAs second mirror 106 has a reflectivity R2 of 99.7%. Al (Al)₉₀The size of the optical window 115 in the GaAs oxide layer 105 is 2-100 μm;

the light emitting units are arranged in a square mode, and the center distance d between adjacent light emitting units₀Set at 40 μm.

The first electrode contact layer 108 is made of Ti/Au/Ge with the thickness of 10nm, 50nm or 30nm, and the second electrode contact layer 109 is made of Au/Ge/Ni with the thickness of 30nm, 20nm or 50 nm; the first electrode contact layer 108 is connected to the first electrode contact region 117 and is connected to the external circuit positive electrode; the second electrode contact layer 109 is connected to the second electrode contact region 118 and is connected to the negative electrode of the external circuit; all the light emitting units are communicated with each other in a parallel connection mode.

Using formulasThe Talbot distance L ≈ 1031.6 μm is calculated, and thus, the fractional Talbot distance D may be used₀L/2. Therefore, the thickness of the substrate layer 101 is reduced to 257.9nm by grinding, thinning and polishing.

Finally, a third reflector 113 is deposited on the substrate layer 101 by evaporation, and the material used is ZnSe or CaF₂The reflectivity R3 is 95%, and the position of the substrate layer 101 corresponding to the center of the distance between the adjacent light-emitting unitsA phase difference compensation film 114 is deposited by evaporation, all of which are ZrO or SiO₂The material can compensate the phase difference of delta phi pi. After stable lasing, high-brightness VCSEL laser with same-phase coherent output can be obtained, and the output wavelength is 940 nm.

The above is only a preferred embodiment of the present invention, and is not intended to limit the present invention, and various modifications and changes will occur to those skilled in the art. Any modification, equivalent replacement, or improvement made within the spirit and principle of the present invention should be included in the protection scope of the present invention.