阅读说明：本技术 一种用于车载雷达的高功率vcsel及其制备方法 (High-power VCSEL for vehicle-mounted radar and preparation method thereof ) 是由 林晓珊 吴春寿 宁如光 杨祺 王苏杰 陈振宇 潘彬 王向武 于 2021-03-30 设计创作，主要内容包括：本发明提供一种用于车载雷达的高功率VCSEL及其制备方法,本发明的高功率VCSEL包括沿生长方向依次生长的GaAs衬底、GaAs缓冲层、N型DBR层、五层有源层、氧化层、P型DBR层和P型GaAs层；所述VCSEL总腔长为5个腔长的整数倍。本发明使用隧穿结实现五个有源层串联,并且通过设计特定的腔长,提高了单位面积内的功率,实现更高功率；同时通过设计不同的势垒高度,解决载流子移动距离,提高辐射复合几率,增加粒子数反转,提高输出功率；通过生长厚度的设计,提高增益,改善驻波场,提高输出功率。(The invention provides a high-power VCSEL for a vehicle-mounted radar and a preparation method thereof, wherein the high-power VCSEL comprises a GaAs substrate, a GaAs buffer layer, an N-type DBR layer, five active layers, an oxide layer, a P-type DBR layer and a P-type GaAs layer which are sequentially grown along the growth direction; the VCSEL total cavity length is an integer multiple of 5 cavity lengths. The invention realizes series connection of five active layers by using the tunneling junction, and improves the power in unit area and realizes higher power by designing the specific cavity length; meanwhile, by designing different barrier heights, the moving distance of a carrier is solved, the radiation recombination probability is improved, the population inversion is increased, and the output power is improved; by the design of growth thickness, gain is improved, standing wave field is improved, and output power is improved.)

1. A high-power VCSEL for a vehicle-mounted radar is characterized by comprising a GaAs substrate, a GaAs buffer layer, an N-type DBR layer, an active layer, an oxidation layer, a P-type DBR layer and a P-type GaAs layer which are sequentially grown along the growth direction;

the total cavity length of the VCSEL is integral multiple of 5 cavity lengths;

the active layer comprises a first active layer, a second active layer, a third active layer, a fourth active layer and a fifth active layer which are sequentially grown along the growth direction;

the first active layer comprises a first waveguide layer, a first quantum well, a first waveguide layer AlxGaAs, a first P-type heavily-doped AlxGaAs and a first N-type heavily-doped InGaP which are sequentially grown along the growth direction;

the second active layer comprises a second waveguide layer, a second quantum well, a second waveguide layer AlxGaAs, a second P-type heavily-doped AlxGaAs and a second N-type heavily-doped InGaP which are sequentially grown along the growth direction;

the third active layer comprises a third waveguide layer, a third quantum well, a third waveguide layer AlxGaAs, a third P-type heavily-doped AlxGaAs and a third N-type heavily-doped InxGaP which are sequentially grown along the growth direction;

the fourth active layer comprises a fourth waveguide layer, a fourth quantum well, a fourth waveguide layer AlxGaAs, a fourth P-type heavily-doped AlxGaAs and a fourth N-type heavily-doped InxGaP which are sequentially grown along the growth direction;

the fifth active layer comprises a fifth waveguide layer, a fifth quantum well and a fifth waveguide layer of AlxGaAs which are grown in sequence along the growth direction.

2. The high-power VCSEL for the vehicle-mounted radar as claimed in claim 1, wherein the first waveguide layer, the second waveguide layer, the third waveguide layer, the fourth waveguide layer and the fifth waveguide layer are grown at a thickness X, a growth temperature of 550-700 ℃, a growth pressure of 50-500mbar, a barrier layer of AlxGaAs, a growth thickness of 5-500nm and a growth pressure of 50-500 mbar; the range of X is 5-500 nm.

3. The high-power VCSEL for the vehicle-mounted radar as claimed in claim 1, wherein well layers of the first quantum well, the second quantum well, the third quantum well, the fourth quantum well and the fifth quantum well are InxGaAs, the growth thickness is 5-10nm, the growth temperature is 550-700 ℃, and the growth pressure is 50-500 mbar; the barrier layer is AlxGaAs, the growth thickness is 5-15nm, the growth temperature is 550-700 ℃, and the growth pressure is 50-500 mbar.

4. The high-power VCSEL for the vehicle-mounted radar as claimed in claim 1, wherein the growth temperature of the first waveguide layer AlxGaAs, the second waveguide layer AlxGaAs, the third waveguide layer AlxGaAs, the fourth waveguide layer AlxGaAs and the fifth waveguide layer AlxGaAs is 600-800 ℃ and the growth pressure is 50-500 mbar.

5. The high-power VCSEL for the vehicle-mounted radar as claimed in claim 1, wherein the growth temperature of the first P-type heavily doped AlxGaAs, the second P-type heavily doped AlxGaAs, the third P-type heavily doped AlxGaAs and the fourth P-type heavily doped AlxGaAs is 600-800 ℃, the growth pressure is 50-500mbar, the V/III ratio is 10-500, the doping source is Mg or C, the concentration value is 5E19-2E20atoms/cm³。

6. The high power VCSEL of claim 1, wherein the first N type heavily doped InGaP, the second N type heavily doped InGaP, and the third N type heavily doped InGaPThe growth temperature of the heavily doped InxGaP and the fourth N-type heavily doped InxGaP is 600-³。

7. The high power VCSEL for vehicle radar of claim 1, wherein the x-ranges of AlxGaAs and InxGaAs in said first waveguide layer, second waveguide layer, third waveguide layer, fourth waveguide layer, fifth waveguide layer, first quantum well, second quantum well, third quantum well, fourth quantum well, and fifth quantum well are each 0.1< x < 0.3.

8. The high power VCSEL for the on-vehicle radar of claim 1, wherein an x range of AlxGaAs in the first waveguide layer AlxGaAs is 0.1< x <0.7, and an x range of AlxGaAs in the second waveguide layer AlxGaAs, the third waveguide layer AlxGaAs, the fourth waveguide layer AlxGaAs, and the fifth waveguide layer AlxGaAs is 0.1< x < 0.6.

9. The high-power VCSEL for the vehicle-mounted radar according to claim 1, wherein x range of AlxGaAs in the first P-type heavily doped AlxGaAs, the second P-type heavily doped AlxGaAs, the third P-type heavily doped AlxGaAs and the fourth P-type heavily doped AlxGaAs is 0< x < 0.3; the x range of the InGaP in the first N-type heavily doped InGaP, the second N-type heavily doped InGaP, the third N-type heavily doped InGaP and the fourth N-type heavily doped InGaP is 0.4< x < 0.6.

10. A method of manufacturing a high power VCSEL for vehicle radar according to any of claims 1-9, comprising the steps of:

s1, growing a GaAs buffer layer on a GaAs substrate;

s2, growing an N-type DBR layer on the GaAs buffer layer;

s3, sequentially growing a first active layer, a second active layer, a third active layer, a fourth active layer and a fifth active layer on the N-type DBR layer;

s4, growing an oxide layer on the fifth waveguide layer AlxGaAs of the fifth active layer;

s5, growing a P-type DBR layer on the oxide layer;

and S6, growing a P-type GaAs layer on the P-type DBR layer.

Technical Field

The invention relates to the technical field of semiconductor lasers, in particular to a high-power VCSEL for a vehicle-mounted radar and a preparation method thereof.

Background

Vertical Cavity Surface Emitting Lasers (VCSELs) have been used in the field of data communications for more than twenty years, but there are many emerging application requirements that are driving the mass production and performance improvements of VCSELs. These applications include, but are not limited to, face recognition, gesture recognition, proximity sensing, high-resolution video display, automotive lidar, infrared illumination, infrared heating, atomic clocks.

The unijunction VCSEL is widely applied to a mobile phone end at present, can only realize the test of a distance of dozens of meters, is difficult to meet the long-distance test, and cannot meet the requirements of a vehicle-mounted radar. Therefore, it is important to develop a vertical cavity laser with higher power in the effective area to realize long-distance testing. Meanwhile, the problem of space hole burning in the unijunction is solved, and the requirement on the module is reduced.

The structure of the VCSEL which is widely used at present is shown in fig. 1, and the preparation method mainly comprises the following steps:

1) growing a GaAs buffer layer 2 on a GaAs substrate 1 at a growth temperature of 600-;

2) the growth temperature of the N-type DBR layer 3 grown on the GaAs buffer layer 2 is 650-800 ℃, the growth pressure is 50mbar, and the growth thickness is 4 mu m;

3) growing a first waveguide layer 4 on the N-type DBR layer 3 at the growth temperature of 650-800 ℃, the growth pressure of 50mbar and the growth thickness of 50 nm;

4) an active layer 5 grows on the first waveguide layer 4, the growth temperature is 650-;

5) growing a second waveguide layer 6 on the active layer 5 at the growth temperature of 650-;

6) growing an oxide layer 7 on the second waveguide layer 6 at the growth temperature of 650-;

7) growing a P-type DBR layer 8 on the oxide layer 7, wherein the growth temperature is 650-;

8) and growing a P-type GaAs layer 9 (0 < x < 0.5) on the grown P-type DBR layer 8 at the growth temperature of 600-800 ℃, the growth pressure of 50mbar and the growth thickness of 0-50 nm.

The VCSEL prepared by the technical method is used for the vehicle-mounted radar and has the following defects:

1. the power is low and only limited to a few watts, so that the high power in the same area is difficult to realize;

2. the gain is relatively low, and the current market requirements cannot be met;

3. the phenomenon of space hole burning is serious;

4. higher order modes are more difficult to control.

Disclosure of Invention

Aiming at the defects of the prior art, the invention provides the high-power VCSEL for the vehicle-mounted radar and the preparation method thereof, which can effectively improve the power, improve the gain spectrum, improve the hole burning phenomenon, reduce the multimode and have longer transmission distance.

The invention realizes a high-power VCSEL for a vehicle-mounted radar by the following technical scheme, which comprises a GaAs substrate, a GaAs buffer layer, an N-type DBR layer, an active layer, an oxidation layer, a P-type DBR layer and a P-type GaAs layer which are sequentially grown along the growth direction;

the total cavity length of the VCSEL is integral multiple of 5 cavity lengths;

the active layer comprises a first active layer, a second active layer, a third active layer, a fourth active layer and a fifth active layer which are sequentially grown along the growth direction;

the first active layer comprises a first waveguide layer, a first quantum well, a first waveguide layer AlxGaAs, a first P-type heavily-doped AlxGaAs and a first N-type heavily-doped InGaP which are sequentially grown along the growth direction;

the second active layer comprises a second waveguide layer, a second quantum well, a second waveguide layer AlxGaAs, a second P-type heavily-doped AlxGaAs and a second N-type heavily-doped InGaP which are sequentially grown along the growth direction;

the third active layer comprises a third waveguide layer, a third quantum well, a third waveguide layer AlxGaAs, a third P-type heavily-doped AlxGaAs and a third N-type heavily-doped InxGaP which are sequentially grown along the growth direction;

the fourth active layer comprises a fourth waveguide layer, a fourth quantum well, a fourth waveguide layer AlxGaAs, a fourth P-type heavily-doped AlxGaAs and a fourth N-type heavily-doped InxGaP which are sequentially grown along the growth direction;

the fifth active layer comprises a fifth waveguide layer, a fifth quantum well and a fifth waveguide layer of AlxGaAs which are grown in sequence along the growth direction.

The technical scheme uses five active regions which are effectively connected in series, and can effectively improve the internal power of unit area.

Furthermore, in the above scheme, the growth thickness of the first waveguide layer, the second waveguide layer, the third waveguide layer, the fourth waveguide layer and the fifth waveguide layer is X, the growth temperature is 550-700 ℃, the growth pressure is 50-500mbar, the barrier layer is AlxGaAs, the growth thickness is 5-500nm, and the growth pressure is 50-500 mbar; the range of X is 5-500 nm.

Furthermore, in the scheme, the well layers of the first quantum well, the second quantum well, the third quantum well, the fourth quantum well and the fifth quantum well are InxGaAs, the growth thickness is 5-10nm, the growth temperature is 550-700 ℃, and the growth pressure is 50-500 mbar; the barrier layer is AlxGaAs, the growth thickness is 5-15nm, the growth temperature is 550-700 ℃, and the growth pressure is 50-500 mbar.

Furthermore, in the scheme, the growth temperature of the first waveguide layer AlxGaAs, the second waveguide layer AlxGaAs, the third waveguide layer AlxGaAs, the fourth waveguide layer AlxGaAs and the fifth waveguide layer AlxGaAs is 600-.

Furthermore, in the above scheme, the first P-type heavily doped AlxGaAs, the second P-type heavily doped AlxGaAs, the third P-type heavily doped AlxGaAs and the fourth P-type heavily doped AlxGaAsThe growth temperature of the type heavily doped AlxGaAs is 600-800 ℃, the growth pressure is 50-500mbar, the V/III ratio is 10-500, the doping source is Mg or C, the concentration value is 5E19-2E20atoms/cm³。

Furthermore, in the above scheme, the growth temperature of the first N-type heavily doped InxGaP, the second N-type heavily doped InxGaP, the third N-type heavily doped InxGaP and the fourth N-type heavily doped InxGaP is 600-800 ℃, the growth pressure is 50-500mbar, the V/III ratio is 10-500, the doping source is Si or Te, and the concentration value is 1E18-5E19atoms/cm³。

Further, in the above scheme, x ranges of AlxGaAs and InxGaAs in the first waveguide layer, the second waveguide layer, the third waveguide layer, the fourth waveguide layer, the fifth waveguide layer, the first quantum well, the second quantum well, the third quantum well, the fourth quantum well, and the fifth quantum well are all 0.1< x < 0.3.

Further, in the above scheme, the x range of alxgas in the first waveguide layer alxgas is 0.1< x <0.7, and the x range of alxgas in the second waveguide layer alxgas, the third waveguide layer alxgas, the fourth waveguide layer alxgas and the fifth waveguide layer alxgas is 0.1< x < 0.6.

Further, in the above scheme, x of alxgas in the first P-type heavily doped alxgas, the second P-type heavily doped alxgas, the third P-type heavily doped alxgas, and the fourth P-type heavily doped alxgas is in a range of 0< x < 0.3.

Further, in the above scheme, the range of x of the InGaP in the first N-type heavily doped InGaP, the second N-type heavily doped InGaP, the third N-type heavily doped InGaP and the fourth N-type heavily doped InGaP is 0.4< x < 0.6.

The invention also provides a preparation method of the high-power VCSEL for the vehicle-mounted radar, which is characterized by comprising the following steps of:

s1, growing a GaAs buffer layer on a GaAs substrate;

s2, growing an N-type DBR layer on the GaAs buffer layer;

s3, sequentially growing a first active layer, a second active layer, a third active layer, a fourth active layer and a fifth active layer on the N-type DBR layer;

s4, growing an oxide layer on the fifth waveguide layer AlxGaAs of the fifth active layer;

s5, growing a P-type DBR layer on the oxide layer;

and S6, growing a P-type GaAs layer on the P-type DBR layer.

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

1. the five active layers are effectively connected in series, so that the internal power of a unit area can be effectively improved;

2. the invention is designed aiming at the optical path of the cavity movement effectively, and can better improve the phenomenon of space hole burning;

3. the invention aims at the design of the tunneling junction, can reduce the internal loss and absorption;

4. according to the invention, through the design of growth thickness, the gain is improved, the standing wave field is improved, and the output power is improved;

5. according to the invention, through designing different barrier heights, the moving distance of a current carrier is solved, the radiation recombination probability is improved, the population inversion is increased, and the output power is improved;

6. the invention realizes the series connection of a plurality of active layers by meeting the requirement of a specific cavity length, thereby realizing higher power.

Drawings

FIG. 1 is a schematic diagram of a prior art VCSEL structure;

FIG. 2 is a schematic diagram of a VCSEL structure prepared by the method of the present invention;

figure 3 is a band diagram of a VCSEL of the present invention.

Number designations in the schematic drawings illustrate that:

1. a GaAs substrate; 2. a GaAs buffer layer; 3. an N-type DBR layer; 4. a first waveguide layer; 5. an active layer; 6. a second waveguide layer; 7. an oxide layer; 8. a P-type DBR layer; 9. a P-type GaAs layer; a1, a first waveguide layer; a2, a first quantum well; a3, first waveguide layer AlxGaAs; a4, first P-type heavily-doped AlxGaAs; a5, first N-type heavily doped InxGaP; b1, a second waveguide layer; b2, a second quantum well; b3, second waveguide layer AlxGaAs; b4, second P-type heavily doped AlxGaAs; b5, second N-type heavily doped InxGaP; c1, a third waveguide layer; c2, a third quantum well; c3, third waveguide layer AlxGaAs; c4, third P-type heavily doped AlxGaAs; c5, third N-type heavily doped InxGaP; d1, a fourth waveguide layer; d2, fourth quantum well; d3, fourth waveguiding layer AlxGaAs; d4, fourth P-type heavily doped AlxGaAs; d5, fourth N-type heavily doped InxGaP; e1, fifth waveguide layer; e2, fifth quantum well; e3, a fifth waveguide layer of AlxGaAs.

Detailed Description

The technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the drawings in the embodiments of the present application, and it is obvious that the described embodiments are only a part of the embodiments of the present application, and not all of the embodiments. The following description of at least one exemplary embodiment is merely illustrative in nature and is in no way intended to limit the application, its application, or uses. 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 application.

In the description of the present application, it should be understood that the terms "first", "second", etc. are used to define the components, and are used only for the convenience of distinguishing the corresponding components, and if not otherwise stated, the terms have no special meaning, and thus, should not be construed as limiting the scope of the present application.

In the description of the present application, it is to be understood that the orientation or positional relationship indicated by the directional terms such as "front, rear, upper, lower, left, right", "lateral, vertical, horizontal" and "top, bottom", etc., are generally based on the orientation or positional relationship shown in the drawings, and are used for convenience of description and simplicity of description only, and in the case of not making a reverse description, these directional terms do not indicate and imply that the device or element being referred to must have a particular orientation or be constructed and operated in a particular orientation, and therefore, should not be considered as limiting the scope of the present application; the terms "inner and outer" refer to the inner and outer relative to the profile of the respective component itself.

Referring to fig. 1 to 2, it should be noted that the drawings provided in the present embodiment are only schematic illustrations of the basic idea of the present invention, and only show the components related to the present invention rather than drawn according to the number, shape and size of the components in actual implementation, the shape, number and ratio of the components in actual implementation may be changed arbitrarily, and the layout of the components may be more complicated.

FIG. 2 is a schematic structural diagram of a high-power VCSEL for a vehicle-mounted radar of the present invention, which includes a GaAs substrate 1, a GaAs buffer layer 2, an N-type DBR layer 3, a first waveguide layer a1, a first quantum well a2, a first waveguide layer AlxGaAs a3, a first P-type heavily doped AlxGaAs a4, a first N-type heavily doped InxGaP a5, a second waveguide layer b1, a second quantum well b2, a second waveguide layer AlxGaAs b3, a second P-type heavily doped AlxGaAs b4, a second N-type heavily doped InxGaP b5, and a third waveguide layer c1, a third quantum well c2, a third waveguide layer AlxGaAs c3, a third P-type heavily doped AlxGaAs c4, a third N-type heavily doped InxGaP c5, a fourth waveguide layer d1, a fourth quantum well d2, a fourth waveguide layer AlxGaAs d3, a fourth P-type heavily doped AlxGaAs d4, a fourth N-type heavily doped InxGaP d5, a fifth waveguide layer e1, a fifth quantum well e2, a fifth waveguide layer AlxGaAs e3, an oxide layer 7, a P-type DBR layer 8 and a P-type GaAs layer 9.

In the embodiment of the invention, a P-type AlxGa (1-x) As layer can be grown on the P-type DBR layer, wherein x is in a range of 0< x < 0.5.

The embodiment provides a preparation method of a high-power VCSEL for a vehicle-mounted radar, which comprises the following steps:

s1, growing a GaAs buffer layer on a GaAs substrate.

Specifically, the growth temperature of step S1 is 600-700 ℃, the growth pressure is 50mbar, and the growth thickness is 10-25 nm.

And S2, growing an N-type DBR layer on the GaAs buffer layer.

Specifically, the growth temperature of the step S2 is 650-800 ℃, the growth pressure is 50mbar, and the growth thickness is 4 mu m.

And S3, sequentially growing a first active layer, a second active layer, a third active layer, a fourth active layer and a fifth active layer on the N-type DBR layer.

Specifically, the growing of the first active layer of step S3 may include:

growing a first waveguide layer on the N-type DBR layer, wherein the growing thickness is X, the range of X is 5-500nm, the growing temperature is 550-700 ℃, and the growing pressure is 50-500 mbar; wherein the base is AlxGaAs, wherein x is within the range of 0.1< x <0.3, the growth thickness is 5-500nm, and the growth pressure is 50-500 mbar;

growing a first quantum well on the first waveguide layer, wherein the well is InxGaAs, x ranges from 0.1 to x <0.3, the growth thickness is 5-10nm, the growth temperature is 550-700 ℃, and the growth pressure is 50-500 mbar; the base is AlxGaAs, wherein x is within the range of 0.1< x <0.3, the growth thickness is 5-15nm, the growth temperature is 550-700 ℃, the growth pressure is 50-500mbar, the growth period is 3-5, and the total growth thickness is A1;

growing a first waveguide layer AlxGaAs on the first quantum well, wherein x ranges from 0.1 to x <0.7, the growth temperature is 600-800 ℃, the growth pressure is 50-500mbar, and the total growth thickness is A2;

growing a first P-type heavily doped AlxGaAs over the first waveguide layer AlxGaAs, wherein x is in the range of 0<x<0.3, the growth temperature is 600-³The total growth thickness is A3;

growing a first N-type heavily doped InxGaP on the first P-type heavily doped AlxGaAs, wherein x is in the range of 0.4<X<0.6, the growth temperature is 600-³And the total growth thickness is A4.

Specifically, the growing of the second active layer of step S3 may include:

growing a second waveguide layer on the first N-type heavily doped InxGaP at the growth temperature of 550-700 ℃ and the growth pressure of 50-500 mbar; wherein the base is AlxGaAs, wherein x is within the range of 0.1< x <0.3, the growth thickness is 5-500nm, the growth pressure is 50-500mbar, and the total growth thickness is B1;

growing a second quantum well on the second waveguide layer, wherein the well is InxGaAs, x is within the range of 0.1< x <0.3, the growth thickness is 5-10nm, the growth temperature is 550-700 ℃, and the growth pressure is 50-500 mbar; the base is AlxGaAs, wherein x is within the range of 0.1< x <0.3, the growth thickness is 5-15nm, the growth temperature is 550-700 ℃, the growth pressure is 50-500mbar, the growth period is 3-5, and the total growth thickness is B2;

growing a second waveguide layer AlxGaAs on the second quantum well, wherein x ranges from 0.1 to x <0.6, the growth temperature is 600-800 ℃, the growth pressure is 50-500mbar, and the total growth thickness is B3;

growing a second P-type heavily doped AlxGaAs over the second waveguide layer AlxGaAs, wherein x is in the range of 0<x<0.3, the growth temperature is 600-³The total growth thickness is B4;

growing a second N-type heavily doped InxGaP on the second P-type heavily doped AlxGaAs, wherein x is in the range of 0.4<X<0.6, the growth temperature is 600-³And the total growth thickness is B5.

Specifically, the growing of the third active layer of step S3 may include:

growing a third waveguide layer on the second N-type heavily doped InxGaP at the growth temperature of 550-700 ℃ and the growth pressure of 50-500mbar, wherein the base is AlxGaAs, the range of x is 0.1< x <0.3, the growth thickness is 5-500nm, the growth pressure is 50-500mbar, and the total growth thickness is C1;

growing a third quantum well on the third waveguide layer, wherein the well is InxGaAs, x ranges from 0.1 to 0.3, the growth thickness is 5-10nm, the growth temperature is 550-700 ℃, and the growth pressure is 50-500 mbar; the base is AlxGaAs, wherein x is within the range of 0.1< x <0.3, the growth thickness is 5-15nm, the growth temperature is 550-700 ℃, the growth pressure is 50-500mbar, the growth period is 3-5, and the total growth thickness is C2;

growing a third waveguide layer AlxGaAs on the third quantum well, wherein x ranges from 0.1 to 0< x <0.6, the growth temperature is 600-800 ℃, the growth pressure is 50-500mbar, and the total growth thickness is C3;

growing a third P-type heavily-doped AlxGaAs on the third waveguide layer AlxGaAs, wherein x is in the range of 0<x<0.3, the growth temperature is 600-³The total growth thickness is C4;

growing a third N-type heavily doped InxGaP on the third P-type heavily doped AlxGaAs, wherein x is in the range of 0.4<X<0.6，The growth temperature is 600-800 ℃, the growth pressure is 50-500mbar, the V/III ratio is 10-500, the doping source is Si or Te, the concentration value is 1E18-5E19atoms/cm³And the total growth thickness is C5.

Specifically, the growing of the fourth active layer of step S3 may include:

growing a fourth waveguide layer on the third N-type heavily doped InxGaP at the growth temperature of 550-700 ℃ and the growth pressure of 50-500mbar, wherein the base is AlxGaAs, the range of x is 0.1< x <0.3, the growth thickness is 5-500nm, the growth pressure is 50-500mbar, and the total growth thickness is D1;

growing a fourth quantum well on the fourth waveguide layer, wherein the well is InxGaAs, x ranges from 0.1 to 0.3, the growth thickness is 5-10nm, the growth temperature is 550-700 ℃, and the growth pressure is 50-500 mbar; the base is AlxGaAs, wherein x is within the range of 0.1< x <0.3, the growth thickness is 5-15nm, the growth temperature is 550-700 ℃, the growth pressure is 50-500mbar, the growth period is 3-5, and the total growth thickness is D2;

growing a fourth waveguide layer AlxGaAs on the fourth quantum well, wherein x ranges from 0.1 to x <0.6, the growth temperature is 600-800 ℃, the growth pressure is 50-500mbar, and the total growth thickness is D3;

growing a fourth P-type heavily doped AlxGaAs on the fourth waveguiding layer AlxGaAs, wherein x is in the range of 0<x<0.3, the growth temperature is 600-³The total growth thickness is D4;

growing a fourth N-type heavily doped InxGaP on the fourth P-type heavily doped AlxGaAs, wherein x is in the range of 0.4<X<0.6, the growth temperature is 600-³And the total growth thickness is D5.

Specifically, the growing of the fifth active layer of step S3 may include:

growing a fifth waveguide layer on the fourth N-type heavily doped InxGaP at the growth temperature of 550-;

growing a fifth quantum well on the fifth waveguide layer, wherein the well is InxGaAs, x is within the range of 0.1< x <0.3, the growth thickness is 5-10nm, the growth temperature is 550-700 ℃, and the growth pressure is 50-500 mbar; the base is AlxGaAs, wherein x is within the range of 0.1< x <0.3, the growth thickness is 5-15nm, the growth temperature is 550-700 ℃, the growth pressure is 50-500mbar, the growth period is 3-5, and the total growth thickness is E2;

and growing a fifth waveguide layer AlxGaAs on the fifth quantum well, wherein x is in a range of 0.1< x <0.6, the growth temperature is 600-800 ℃, the growth pressure is 50-500mbar, and the total growth thickness is E3.

The embodiment completes the growth of five active layers, effectively connects a plurality of active layers in series by designing the specific cavity length, improves the power in unit area and realizes higher power.

Preferably, in embodiments where the cavity length satisfies X × N + a1 × N1+ E3 × N3= λ × N (N =1,2,3 …), the fundamental optical field can be realized mainly by satisfying the first pair of optical cavities, where λ is the cavity length and N, N1, N3 are the refractive indices corresponding to the Al component of each layer thickness.

Preferably, in the embodiment, when the cavity length satisfies B1 × N5+ B2 × N6+ B3 × N7+ B4 × N8+ B5 × N9 =1/2 λ × N (N =1,2,3 …), the second pair of optical cavities is mainly satisfied, so that carrier maximization is achieved, the probability of radiation recombination is improved, the gain is improved, the standing wave field is improved, and the output power is improved, wherein λ is the cavity length, and N5, N6, N7, N8, and N9 are refractive indexes corresponding to Al components of each layer thickness.

Preferably, in the embodiment, when the cavity length satisfies C1 × N5+ C2 × N6+ C3 × N7+ C4 × N8+ C5 × N9 =3/2 λ × N (N =1,2,3 …), the third pair of optical cavities is mainly satisfied, so as to realize the correction, increase the gain, improve the standing wave field, and increase the output power, where λ is the cavity length, and N5, N6, N7, N8, and N9 are refractive indexes corresponding to Al components in each layer thickness.

Preferably, in the embodiment, when the cavity length satisfies D1 × N5+ D2 × N6+ D3 × N7+ D4 × N8+ D5 × N9 =1/2 λ × N (N =1,2,3 …), the fourth pair of optical cavities is mainly satisfied, so that carrier maximization is achieved, the increase of the radiation recombination probability is facilitated, the gain is improved, the standing wave field is improved, and the output power is improved, wherein λ is the cavity length, and N5, N6, N7, N8, and N9 are refractive indexes corresponding to Al components in each layer thickness.

Preferably, in the embodiment, when the cavity length satisfies a2 × N2+ A3 × N3+ a4 × N8+ E1 × N5+ E2 × N6 =3/2 λ × N (N =1,2,3 …), the fifth pair of optical cavities is mainly satisfied, so that the correction is realized, the gain is increased, the standing wave field is improved, and the output power is increased, where λ is the cavity length, and N2, N3, N5, N6, and N8 are refractive indexes corresponding to Al components in each layer thickness.

Specifically, the total cavity length of the VCSEL in the present invention satisfies (λ +1/2 λ +3/2 λ +1/2 λ +3/2 λ) × N =5 λ × N (N =1,2,3 …), and the output power is significantly improved.

As can be seen from the band values in fig. 3, the position of the optical field in the active layer is changed by the refractive indexes of different band material thicknesses, so that the loss is reduced, and the non-radiative recombination is reduced, thereby achieving a lower catastrophe effect, increasing the differential gain, improving the carrier confinement, and increasing the output power.

And S4, growing an oxide layer on the fifth waveguide layer AlxGaAs of the fifth active layer.

Specifically, in step S4, an oxide layer is grown on the fifth waveguide layer, wherein the growth temperature is 650-.

And S5, growing a P-type DBR layer on the oxide layer.

Specifically, in the step S5, a P-type DBR layer grows on the oxide layer, the growth temperature is 650-800 ℃, the growth pressure is 50mbar, and the growth thickness is 3 mu m.

And S6, growing a P-type GaAs layer on the P-type DBR layer.

Specifically, in step S6, a P-type AlxGa (1-x) As (0 < x < 0.5) layer may be grown on the growth P-type DBR layer at a growth temperature of 600-; or growing a P-type GaAs layer on the P-type DBR layer at 600-800 deg.C under 50mbar and 0-50 nm.

In conclusion, the five active layers are connected in series by using the tunneling junctions, and the power in unit area is improved and higher power is realized by designing the specific cavity length; by designing different barrier heights, the moving distance of a carrier is solved, the radiation recombination probability is improved, the population inversion is increased, and the output power is improved; through the design of growth thickness, gain is improved, standing wave field is improved, output power is improved, high power is achieved overall, and the distance test of the vehicle-mounted radar of 100-200 meters can be met.

Finally, it should be emphasized that the above-described preferred embodiments of the present invention are merely examples of implementations, rather than limitations, and that many variations and modifications of the invention are possible to those skilled in the art, without departing from the spirit and scope of the invention.