WO2021213233A1

WO2021213233A1 - Vertical cavity surface emitting laser, manufacturing method thereof and camera module

Info

Publication number: WO2021213233A1
Application number: PCT/CN2021/087286
Authority: WO
Inventors: 罗杰; 万叶晶; 毛信贤
Original assignee: 江西欧迈斯微电子有限公司
Priority date: 2020-04-22
Filing date: 2021-04-14
Publication date: 2021-10-28
Also published as: CN111509560A

Abstract

A vertical cavity surface emitting laser (100), comprising: a substrate (10); a first distributed Bragg reflector (20) arranged on one side of the substrate (10); an active layer (30) stacked on the side of the first distributed Bragg reflector (20) away from the substrate (10); a high resistance layer (40) arranged on the side of the active layer (30) away from the substrate (10) and provided with an aperture (42); a second distributed Bragg reflector (50) arranged in the aperture (42) and connected to the active layer (30); a first electrode (60) connected to the substrate (10); and a second electrode (70) arranged on the side of the second distributed Bragg reflector (50) away from the substrate (10). The light-emitting aperture size can be precisely controlled, and the heat dispersion effect is better. Also provided is a manufacturing method for the vertical cavity surface emitting laser (100) and a camera module.

Description

Vertical cavity surface emitting laser, preparation method and camera module

Technical field

The invention relates to the technical field of semiconductor lasers, in particular to a vertical cavity surface emitting laser, a preparation method and a camera module.

Background technique

Vertical-Cavity Surface-Emitting Laser (VCSEL), its resonant cavity is used to form two distributed Bragg reflectors with high reflectivity on the upper and lower sides of the active region (Active region). , Referred to as DBR), the laser is emitted vertically along the epitaxial growth direction of the material. The vertical cavity surface emitting laser has a circular spot, easy to couple with optical fiber, easy to realize the advantages of large-scale array and optoelectronic integration, and is widely used in optical communications, mobile phones, precision processing, advanced manufacturing equipment, testing instruments and other fields.

The light-emitting aperture of the vertical cavity surface emitting laser determines the divergence angle, uniformity, and heat dissipation functions. At present, the light-emitting aperture of the vertical cavity surface emitting laser is usually realized by lateral oxidation. After all the layers of the vertical cavity surface emitting laser are fabricated, they are mesa-etched and then laterally oxidized to achieve the control of the light-emitting aperture. However, the prior art has at least the following shortcomings: the manufacturing process of the light-emitting aperture is complicated; the size of the oxide aperture cannot be accurately controlled, and the divergence angle and uniformity of the vertical cavity surface emitting laser cannot be guaranteed; and the thermal conductivity of oxide is relatively high. Low, and the generated oxide layer has a poor heat dissipation effect, which affects the heat dissipation effect of the vertical cavity surface emitting laser.

Summary of the invention

In view of the above content, it is necessary to propose a vertical cavity surface emitting laser, a preparation method of a vertical cavity surface emitting laser, and a camera module to solve the above problems.

An embodiment of the present application provides a vertical cavity surface emitting laser, including:

Substrate

The first distributed Bragg reflector is arranged on one side of the substrate;

An active layer stacked on the side of the first distributed Bragg reflector away from the substrate;

A high-resistance layer arranged on the side of the active layer away from the substrate, and a light-through hole is opened in the high-resistance layer;

The second distributed Bragg reflector is arranged in the light-passing hole and connected to the active layer;

The first electrode is connected to the substrate; and

The second electrode is arranged on the side of the second distributed Bragg reflector away from the substrate.

The vertical cavity surface emitting laser provided in the above embodiment controls the light emitting aperture by opening a light hole on the high resistance layer, which solves the problem of difficult control of the light emitting aperture size, can precisely control the light emitting aperture, and further ensures the vertical cavity surface emission The emission angle and uniformity of the laser; and, due to the high thermal conductivity of the high resistance layer, the heat dissipation effect of the vertical cavity surface emitting laser is also improved.

In some embodiments, the high resistance layer is one of silicon nitride, boron nitride, and aluminum nitride. The high-resistance layer serves as a current confinement area, which determines the size of the light-emitting aperture of the vertical cavity surface emitting laser. The high-resistance layer is a material with high resistance and high thermal conductivity, which can not only accurately control the size of the light-emitting aperture, but also improve the heat dissipation effect.

In some embodiments, along the stacking direction of the first distributed Bragg reflector and the second distributed Bragg reflector, the thickness of the high resistance layer is the same as the thickness of the second distributed Bragg reflector , So that the high-resistance layer can surround the second distributed Bragg reflector to limit the light-emitting aperture.

In some embodiments, the substrate is a gallium arsenide substrate, and the first distributed Bragg reflector and the second distributed Bragg reflector respectively include a plurality of alternately arranged aluminum arsenide layers and arsenide layers. The gallium layer or each includes a plurality of alternately arranged aluminum gallium arsenide layers and gallium arsenide layers, so that the first distributed Bragg reflector and the second distributed Bragg reflector have high reflectivity.

The embodiment of the present application also provides a method for manufacturing a vertical cavity surface emitting laser, including:

Epitaxially grow a first distributed Bragg reflector and an active layer, the first distributed Bragg reflector and the active layer are sequentially arranged on one side of the substrate;

Forming a high-resistance layer, the high-resistance layer disposed on the side of the active layer away from the substrate;

Etching the high-resistance layer, the active layer, and the first distributed Bragg reflector to form a boss, and etching the high-resistance layer to form a light through hole in the high-resistance layer;

Epitaxially grow a second distributed Bragg reflector, the second distributed Bragg reflector is located in the light-passing hole and connected to the active layer;

A first electrode and a second electrode are formed, the first electrode is arranged on a side of the substrate, and the second electrode is arranged on a side of the second distributed Bragg reflector away from the substrate.

The preparation method of the vertical cavity surface emitting laser provided by the above embodiment firstly forms a high resistance layer above the active layer, and then etches a light hole in the high resistance layer, which solves the problem that the light-emitting aperture size is difficult to control and can be precisely controlled The light-emitting aperture ensures the emission angle and uniformity of the vertical cavity surface emitting laser; the preparation method has a simple process, does not require a lateral oxidation process, and improves the preparation efficiency. At the same time, due to the high thermal conductivity of the high resistance layer, the heat dissipation performance of the vertical cavity surface emitting laser is also improved.

In some embodiments, "etch the high-resistance layer, the active layer, and the first distributed Bragg mirror to form bumps, and etch the high-resistance layer to form in the high-resistance layer The steps of "clearing hole" include:

A photoresist film is formed on the surface of the high-resistance layer, a part of the photoresist film in the peripheral area of the high-resistance layer is removed by photolithography, and the high-resistance layer, the active layer and the A first distributed Bragg reflector to form the boss;

Using an organic solvent to remove a part of the photoresist film located in the middle of the boss;

Using an etching solution to etch a portion of the high resistance layer that does not cover the photoresist film to form the light through hole, and the light through hole exposes the active layer;

The remaining photoresist film is removed.

In the above embodiment, the high-resistance layer is etched under the protection of the photoresist film, so that the shape and size of the light-passing hole can be precisely controlled.

In some embodiments, the high resistance layer is one of silicon nitride, boron nitride, and aluminum nitride. The high-resistance layer serves as a current confinement area, which determines the size of the light-emitting aperture of the vertical cavity surface emitting laser. The high-resistance layer is made of a material with high resistance and high thermal conductivity, which can not only accurately control the size of the light-emitting aperture, but also improve the heat dissipation effect.

In some embodiments, the chemical vapor deposition method is used to form the high resistance layer, which has the advantages of easy control of the film composition, the film thickness is proportional to the deposition time, and the uniformity is better.

The present application also provides a camera module including the vertical cavity surface emitting laser provided by any of the above embodiments.

The camera module includes a vertical cavity surface emitting laser. The light-emitting aperture is controlled by opening a light hole on the high-resistance layer, which solves the problem that the light-emitting aperture is difficult to control, so that the light-emitting aperture can be accurately controlled and can ensure The emission angle and uniformity of the vertical cavity surface emitting laser; and, due to the high thermal conductivity of the high resistance layer, the heat dissipation effect of the vertical cavity surface emitting laser and the camera module is also improved.

Description of the drawings

FIG. 1 is a schematic diagram of a cross-sectional structure of a vertical cavity surface laser transmitter according to a first embodiment of the present invention.

FIG. 2 is a flowchart of a method for manufacturing a vertical cavity surface laser transmitter according to a second embodiment of the present invention.

3 to 7 are schematic diagrams of the manufacturing method of the vertical cavity surface laser transmitter according to the second embodiment of the present invention.

Symbol description of main components

Vertical cavity surface emitting laser 100

Substrate 10

The first distributed Bragg reflector 20

Active layer 30

High resistance layer 40

Light hole 42

The second distributed Bragg reflector 50

First electrode 60

Second electrode 70

Passivation layer 80

Detailed ways

In order to make the objectives, technical solutions, and advantages of the present invention clearer, the following further describes the present invention in detail with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described here are only used to explain the present invention, but not used to limit the present invention. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative work shall fall within the protection scope of the present invention.

It should be further noted that, in this article, the terms "include", "include" or any other variants thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements not only includes those elements , And also include other elements not explicitly listed, or elements inherent to the process, method, article, or device. If there are no more restrictions, the element defined by the sentence "including a..." does not exclude the existence of other identical elements in the process, method, article, or device that includes the element.

Referring to FIG. 1, the first embodiment of the present invention provides a vertical cavity surface emitting laser 100, which includes a substrate 10, a first distributed Bragg reflector 20, an active layer 30, a high resistance layer 40, and a second distribution Type Bragg reflector 50, first electrode 60 and second electrode 70. In this embodiment, the first distributed Bragg reflector 20 is an N-type, and the second distributed Bragg reflector 50 is a P-type.

In this embodiment, the substrate 10 is a gallium arsenide substrate, but is not limited to this. The substrate 10 may also be an indium phosphide substrate, a gallium nitride substrate, an indium antimonide substrate, or the like.

The first distributed Bragg reflector 20 is provided on one side of the substrate 10. In this embodiment, the first distributed Bragg reflector 20 includes a plurality of alternately arranged aluminum arsenide (AlAs) layers and gallium arsenide (GaAs) layers, and the refractive indexes of the aluminum arsenide layer and the gallium arsenide layer are different. The numbers of the aluminum arsenide layer and the gallium arsenide layer are respectively multiple layers, so that the first distributed Bragg reflector 20 has a high reflectivity, wherein the reflectance of the first distributed Bragg reflector 20 can reach 99.99%.

In another embodiment, the first distributed Bragg mirror 20 includes a plurality of aluminum gallium arsenide (AlGaAs) layers and gallium arsenide layers alternately arranged. The numbers of the aluminum gallium arsenide layer and the gallium arsenide layer are respectively multiple layers, which can also enable the first distributed Bragg reflector 20 to have high reflectivity.

The active layer 30 is stacked on the side of the first distributed Bragg reflector 20 away from the substrate 10, and the active layer 30 is used to convert electrical energy into light energy. In an embodiment, the active layer 30 may include indium gallium arsenide (INGaAs) or aluminum gallium arsenide. The active layer 30 can cover the first distributed Bragg reflector 20, along the stacking direction of the first distributed Bragg reflector 20 and the second distributed Bragg reflector 50, the active layer 30 and the first distributed Bragg reflector The widths of the cross sections of 20 are equal.

The high-resistance layer 40 is provided on the side of the active layer 30 away from the substrate 10, and the high-resistance layer 40 is provided with a light-passing hole 42. The light-passing hole 42 is a through hole penetrating the high-resistance layer 40, and the light-passing hole 42 It is one of circular holes and polygonal holes. Preferably, along the stacking direction of the first distributed Bragg reflector 20 and the second distributed Bragg reflector 50, the width of the cross section of the high resistance layer 40 and the active layer 30 are equal.

The high-resistance layer 40 serves as a current limiting area, which can limit the range of current injection, and determines the size of the light-emitting aperture of the vertical cavity surface emitting laser 100. The high resistance layer 40 is a material with high resistance and high thermal conductivity.

The high resistance layer 40 may be one of silicon nitride (SiN), boron nitride (BN), and aluminum nitride (AlN). In one embodiment, the high-resistance layer 40 is silicon nitride (SiN). The resistivity of silicon nitride can reach 1015Ω.cm-1016Ω.cm, and the thermal conductivity is 5-10 times that of aluminum oxide. It is not easy to expand when heated. The internal stress is small.

Preferably, along the stacking direction of the first distributed Bragg reflector 20 and the second distributed Bragg reflector 50, the thickness of the high resistance layer 40 is the same as the thickness of the second distributed Bragg reflector 50, so that the high resistance layer 40 can surround the second distributed Bragg reflector 50 to limit the light-emitting aperture. In some embodiments, the thickness of the high resistance layer 40 may also be slightly larger than the thickness of the second distributed Bragg reflector 50.

The second distributed Bragg reflector 50 is disposed in the light-passing hole 42 and connected to the active layer 30. In an embodiment, the second distributed Bragg reflector 50 includes a plurality of alternately arranged aluminum arsenide layers and gallium arsenide layers. The distributed Bragg reflector 50 has a high reflectivity, wherein the reflectivity of the second distributed Bragg reflector can reach 99%.

In another embodiment, the second distributed Bragg mirror 50 includes a plurality of alternately arranged aluminum gallium arsenide and gallium arsenide layers.

The first electrode 60 is connected to the substrate 10, and the second electrode 70 is provided on the side of the second distributed Bragg reflector 50 away from the substrate 10. The first electrode 60 and the second electrode 70 are used to connect a power supply to apply an electric field to the active layer 30, so that the active layer 30 converts electrical energy into light energy. The first electrode 60 and the second electrode 70 are made of an ohmic contact material, and the ohmic contact material may include at least one of nickel (Ni), gold (Au), palladium (Pd), and silver (Ag).

The first electrode 60 is an N-type electrode. The first electrode 60 can be a strip electrode located on the side of the substrate 10 facing the first distributed Bragg reflector 20, and passes through a via hole opened on the substrate 10 (Figure Not shown) is connected to the side of the substrate 10 away from the first distributed Bragg reflector 20. It can be understood that the first electrode 60 may also adopt the structure of an electrode of an existing vertical cavity surface emitting laser.

In another embodiment, the first electrode 60 may also be a planar electrode and located on the side of the substrate 10 away from the first distributed Bragg reflector 20.

The second electrode 70 is a P-type electrode, and the second electrode 70 is a ring-shaped electrode, which is located on the periphery of the second distributed Bragg reflector 50 and surrounds the light-passing hole 42.

In an embodiment, the vertical cavity surface emitting laser 100 further includes a passivation layer 80, which is provided on the substrate 10 and located on the high resistance layer 40, the active layer 30, and the first distributed Bragg reflector 20. Perimeter. The material of the passivation layer 80 may be resin, which plays a role of planarization and protection. Along the stacking direction of the first distributed Bragg reflector 20 and the second distributed Bragg reflector 50, the height of the passivation layer 80 may be the same as the height of the second distributed Bragg reflector 50.

The vertical cavity surface emitting laser 100 provided by the above embodiment includes a high-resistance layer 40 provided on the active layer 30, a light-passing hole 42 is opened in the high-resistance layer 40, and a second distributed Bragg reflector 50 is provided on the light-passing layer. The hole 42 is connected to the active layer 30. Since the high resistance layer 40 has a high resistance value, the current range can be limited, so that the light-emitting aperture of the vertical cavity surface emitting laser 100 can be controlled. Therefore, the above-mentioned vertical cavity surface emitting laser 100 controls the light-emitting aperture by opening the through hole 42 on the high-resistance layer 40, which solves the problem that the light-emitting aperture is difficult to control, so that the size of the light-emitting aperture can be precisely controlled, and the vertical cavity can be guaranteed. The emission angle and uniformity of the surface emitting laser 100; and, due to the high thermal conductivity of the high resistance layer 40, the heat dissipation effect of the vertical cavity surface emitting laser 100 is also improved.

2 to 7 at the same time, the second embodiment of the present invention provides a method for manufacturing a vertical cavity surface emitting laser 100, including the following steps.

In step S101, the first distributed Bragg reflector 20 and the active layer 30 are epitaxially grown, and the first distributed Bragg reflector 20 and the active layer 30 are sequentially arranged on one side of the substrate 10.

As shown in FIG. 3, the first distributed Bragg reflector 20 and the active layer 30 are sequentially stacked on the substrate 10. In this embodiment, the substrate 10 is a gallium arsenide substrate, but is not limited to this. The substrate 10 may also be an indium phosphide substrate, a gallium nitride substrate, an indium antimonide substrate, or the like.

In an embodiment, the first distributed Bragg mirror 20 includes a plurality of alternately grown aluminum arsenide layers and gallium arsenide layers. When the first distributed Bragg reflector 20 is epitaxially grown, trimethylaluminum, trimethylgallium, and ammonia are used as source gases to alternately grow aluminum arsenide layers and gallium arsenide layers.

Specifically, the substrate 10 is heat-treated at a high temperature of 1100°C under hydrogen for 10 minutes, then the temperature is reduced to 572°C, a layer of 25nm thick low-temperature aluminum arsenide nucleation layer is deposited at a low temperature, and then the temperature is increased to 1135 ℃, grow a 1.3μm gallium arsenide buffer layer. Then, the growth temperature was adjusted to 1030°C, and the aluminum arsenide layer and the gallium arsenide layer were alternately grown in a hydrogen atmosphere to prepare the first distributed Bragg reflector 20. The numbers of the aluminum arsenide layer and the gallium arsenide layer were respectively large Layers, different alternating layers can form different reflectivities, and finally form the first distributed Bragg reflector 20 with a reflectivity of 99.99%.

The active layer 30 may include indium gallium arsenide or aluminum gallium arsenide, and is stacked on the side of the first distributed Bragg reflector 20 away from the substrate 10.

In step S102, a high-resistance layer 40 is formed, and the high-resistance layer 40 is provided on the side of the active layer 30 away from the substrate 10.

As shown in FIG. 4, the high-resistance layer 40 is stacked on the active layer 30, and the high-resistance layer 40 is made of a material with high resistance and high thermal conductivity, and serves as a current confinement area.

In one embodiment, the high resistance layer 40 is a silicon nitride layer. Silicon nitride is an insulating material with high thermal conductivity and low internal stress.

In one embodiment, the high resistance layer 40 is formed by a chemical vapor deposition method. When the high resistance layer 40 is formed by the chemical vapor deposition method, the film composition is easy to control, the film thickness is proportional to the deposition time, and the uniformity is good.

When the high-resistance layer 40 is silicon nitride, the step is specifically as follows: using silane (SiH4) and ammonia (NH3) as gas sources, mixing silane and ammonia into the integrated high-temperature furnace; emitting the vertical cavity surface The wafer of the laser 100 is placed in a high-temperature furnace; silane and ammonia gas chemically react to form a silicon nitride film. The reaction formula is: SiH4+NH3=SiN+H2.

In other embodiments, the high resistance layer 40 can also be made of other materials with high resistance and high thermal conductivity, such as boron nitride (BN) or aluminum nitride (AlN). In step S102, the high resistance layer 40 may also be formed by other methods.

In step S103, the first distributed Bragg reflector 20, the active layer 30 and the high resistance layer 40 are etched to form bumps, and the high resistance layer 40 is etched to form a light-through hole 42 in the high resistance layer 40.

Referring to FIG. 5 at the same time, in one embodiment, the high resistance layer 40, the active layer 30, and the first distributed Bragg reflector 20 are etched first by photolithography to form what is required by the vertical cavity surface emitting laser 100 The boss includes a high-resistance layer 40, an active layer 30, and a first distributed Bragg reflector 20 that are stacked, and along the stacking direction, the high-resistance layer 40, the active layer 30, and the first distributed Bragg reflector The cross-sectional width of 20 can be equal, so that the boss can be a cylindrical table body.

Next, referring to FIG. 6, a light-through hole 42 is etched in the high-resistance layer 40, the light-through hole 42 penetrates the middle of the high-resistance layer 40, and the light-through hole 42 exposes the active layer 30.

In one embodiment, step S103 specifically includes: first forming a photoresist film on the surface of the high resistance layer 40, removing part of the photoresist film in the peripheral area of the high resistance layer 40 by photolithography, and etching the high resistance layer 40, The active layer 30 and the first distributed Bragg reflector 20 form a boss; an organic solvent is used to remove part of the photoresist film located in the middle of the boss, and then an etching solution is used to treat the part of the high resistance layer 40 that is not covered with the photoresist film. Etching is performed to form the light through hole 42, and then the remaining photoresist film is removed.

When the high-resistance layer 40 is silicon nitride, a photoresist film is plated on the surface of the chip generated to the high-resistance layer 40, and the photoresist film is coated with a photoresist; a photolithography mask is provided, and the high-resistance layer 40 is removed after exposure Part of the photoresist film in the peripheral area is etched, and the high resistance layer 40, the active layer 30, and the first distributed Bragg reflector 20 are etched to form the boss. Then, a photoresist mask is provided, and after exposure, a part of the photoresist film in the middle of the boss is removed with an organic solvent. Under the irradiation of ultraviolet light or other appropriate wavelength light, the photoresist changes and its strength is increased, and it is insoluble in organic solvents; while the parts that are not irradiated by light, the photoresist does not change and can be organic The solvent dissolves, so part of the photoresist can be removed with an organic solvent after exposure.

Then, using a hydrofluoric acid (HF) etching solution, the part of the high resistance layer 40 that is not covered by the photoresist film is etched away until the active layer 30 is exposed. The reaction formula is: SiN+HF=SiF4+NH3; at the same time, there is The area covered by the photoresist remains intact.

Then, the remaining photoresist is removed, for example, concentrated sulfuric acid is used to peel off the photoresist, and after cooling, it is rinsed with ionized water. In the above embodiment, the middle portion of the high resistance layer 40 is etched under the protection of the photoresist film, so that the size of the light-passing hole 42 can be precisely controlled.

It can be understood that by controlling the shape of the photoresist film, the shape of the light-passing hole 42 can be controlled. Therefore, the light-passing hole 42 can be set as a circular hole or a polygonal hole as required.

In another embodiment, a photolithography method may also be used to perform the first etching to form the boss; and then the photolithography method may be used to perform the second etching to etch the light-through hole 42.

In step S104, a second distributed Bragg reflector 50 is epitaxially grown, and the second distributed Bragg reflector 50 is located in the light-passing hole 42.

As shown in FIG. 7, the second distributed Bragg reflector 50 is located in the through hole 42 and connected to the active layer 30.

The process of epitaxially growing the second distributed Bragg reflector 50 is substantially the same as that of the first distributed Bragg reflector 20. The difference is that it is the same as the alternately grown aluminum arsenide layer and gallium arsenide in the first distributed Bragg reflector 20. The number of layers is different, and a second distributed Bragg reflector 50 with a reflectivity of 99% is formed.

Preferably, along the stacking direction of the first distributed Bragg reflector 20 and the second distributed Bragg reflector 50, the thickness of the high resistance layer 40 is equal to the thickness of the second distributed Bragg reflector 50, so that the high resistance The layer 40 surrounds the second distributed Bragg reflector 50 to limit the light-emitting aperture. Therefore, the thickness of the high resistance layer 40 can be controlled according to the preset thickness of the second distributed Bragg reflector 50. In some embodiments, the thickness of the high resistance layer 40 may also be slightly larger than the thickness of the second distributed Bragg reflector 50.

In step S105, the first electrode 60 and the second electrode 70 are formed.

1 again, the first electrode 60 is connected to the substrate 10, and the second electrode 70 is located on the side of the second distributed Bragg reflector 50 away from the substrate 10.

Specifically, the first electrode 60 is an N-type electrode, and the first electrode 60 may be a strip electrode and is connected to a side of the substrate 10 away from the first distributed Bragg reflector 20 through a via hole.

In another embodiment, the first electrode 60 can also be a planar electrode and is directly disposed on the side of the substrate 10 away from the first distributed Bragg reflector 20.

In one embodiment, an ohmic contact material is deposited on the surface of the wafer by vacuum evaporation, sputtering, electroplating, etc., the ohmic contact material can be at least one of nickel, gold, palladium, and silver, and then Alloying at a certain temperature. In a high vacuum, resistance heating or electron beam bombardment heating is used to melt the evaporated material. Under low pressure, the atoms on the surface of the melted evaporation material gain enough energy to escape from the evaporation source, thereby depositing a layer of contact material.

In other embodiments, in steps S101 and S104, both the first distributed Bragg reflector 20 and the second distributed Bragg reflector 50 may include alternately grown layers of aluminum gallium arsenide and gallium arsenide.

Please refer to FIG. 1 at the same time. In other embodiments, after step S105, the method may further include the steps of depositing a passivation layer 80 on the substrate 10 and etching the passivation layer 80.

The passivation layer 80 is located on the periphery of the high resistance layer 40, the active layer 30, and the first distributed Bragg reflector 20, and along the stacking direction of the first distributed Bragg reflector 20 and the second distributed Bragg reflector 50, The height of the passivation layer 80 may be the same as the height of the second distributed Bragg reflector 50. The material of the passivation layer 80 may be resin, which plays a role of planarization and protection.

Specifically, the surface of the wafer is cleaned first, for example, first washed with acetone, then rinsed with water and dried in the oven, and then coated with an adhesion promoter on the wafer, and then the passivation layer 80 is coated with equipment at different speeds On the surface of the wafer, pattern etching is performed after oven drying.

In the preparation method of the vertical cavity surface emitting laser 100 provided by the foregoing embodiment, a high resistance layer 40 is first formed on the active layer 30, and then the through hole 42 is etched in the high resistance layer 40, so that the high resistance layer serves as a current confinement area , Can precisely control the size of the light-emitting aperture, and ensure the emission angle and uniformity of the vertical cavity surface emitting laser 100; the preparation method is simple in process, does not require a lateral oxidation process, and solves the problem of the difficulty of precision when making the light hole by the lateral oxidation method. The problem of control improves the preparation efficiency. At the same time, due to the high thermal conductivity of the high resistance layer 40, the heat dissipation performance of the vertical cavity surface emitting laser 100 is also improved.

The third embodiment of the present application provides a camera module including the vertical cavity surface emitting laser 100 provided in the above embodiment. The camera module also includes a receiving module. The vertical cavity surface emitting laser 100 is used to send out signals, and the receiving module is used to receive signals, so that the camera module obtains the signals from the vertical cavity surface emitting laser 100 and the signals received by the receiving module. Information about the object.

The fourth embodiment of the present application provides a camera module, including the vertical cavity surface emitting laser 100 prepared by the vertical cavity surface emitting laser manufacturing method provided in the above embodiments.

The above-mentioned camera module includes a vertical cavity surface emitting laser 100, and the light emitting aperture is controlled by opening a light hole 42 on the high resistance layer 40, so that the size of the light emitting aperture can be precisely controlled, and the emission of the vertical cavity surface emitting laser 100 can be ensured. Angle and uniformity; and, due to the high thermal conductivity of the high resistance layer 40, the heat dissipation effect of the vertical cavity surface emitting laser 100 and the camera module is also improved.

For those skilled in the art, it is obvious that the present invention is not limited to the details of the above exemplary embodiments, and the present invention can be implemented in other specific forms without departing from the spirit or basic characteristics of the present invention. Therefore, from any point of view, the embodiments should be regarded as exemplary and non-limiting. The scope of the present invention is defined by the appended claims rather than the above description, and therefore it is intended to fall within the claims. All changes within the meaning and scope of the equivalent elements of are included in the present invention.

Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and not to limit them. Although the present invention has been described in detail with reference to the preferred embodiments, those of ordinary skill in the art should understand that the technical solutions of the present invention can be Modifications or equivalent replacements are made without departing from the spirit and scope of the technical solution of the present invention.

Claims

A vertical cavity surface emitting laser, characterized in that it comprises:

Substrate

The first distributed Bragg reflector is arranged on one side of the substrate;

An active layer stacked on the side of the first distributed Bragg reflector away from the substrate;

A high-resistance layer arranged on the side of the active layer away from the substrate, and a light-through hole is opened in the high-resistance layer;

The second distributed Bragg reflector is arranged in the light-passing hole and connected to the active layer;

The first electrode is connected to the substrate; and

The second electrode is arranged on the side of the second distributed Bragg reflector away from the substrate.
The vertical cavity surface emitting laser of claim 1, wherein the high resistance layer is one of silicon nitride, boron nitride, and aluminum nitride.
The vertical cavity surface emitting laser of claim 1 or 2, wherein along the stacking direction of the first distributed Bragg reflector and the second distributed Bragg reflector, the thickness of the high resistance layer is The thickness is the same as that of the second distributed Bragg reflector.
The vertical cavity surface emitting laser of claim 1, wherein the substrate is a gallium arsenide substrate, and the first distributed Bragg reflector and the second distributed Bragg reflector respectively comprise multiple There are two alternately arranged aluminum arsenide layers and gallium arsenide layers, or a plurality of alternately arranged aluminum gallium arsenide layers and gallium arsenide layers.
A preparation method of a vertical cavity surface emitting laser, including:

Epitaxially grow a first distributed Bragg reflector and an active layer, the first distributed Bragg reflector and the active layer are sequentially arranged on one side of the substrate;

Forming a high-resistance layer, the high-resistance layer being arranged on the side of the active layer away from the substrate;

Etching the high-resistance layer, the active layer, and the first distributed Bragg reflector to form a boss, and etching the high-resistance layer to form a light through hole in the high-resistance layer;

Epitaxially grow a second distributed Bragg reflector, the second distributed Bragg reflector is located in the light-passing hole and connected to the active layer;

A first electrode and a second electrode are formed, the first electrode is arranged on a side of the substrate, and the second electrode is arranged on a side of the second distributed Bragg reflector away from the substrate.
5. The manufacturing method of claim 5, wherein the high-resistance layer, the active layer and the first distributed Bragg reflector are etched to form bosses, and the high-resistance layer is etched to The step of forming a light-through hole in the high resistance layer includes:

A photoresist film is formed on the surface of the high-resistance layer, a part of the photoresist film in the peripheral area of the high-resistance layer is removed by photolithography, and the high-resistance layer, the active layer and the A first distributed Bragg reflector to form the boss;

Using an organic solvent to remove a part of the photoresist film located in the middle of the boss;

Using an etching solution to etch a portion of the high resistance layer that does not cover the photoresist film to form the light through hole, and the light through hole exposes the active layer;

The remaining photoresist film is removed.
The preparation method according to claim 5, wherein the high resistance layer is one of silicon nitride, boron nitride, and aluminum nitride.
The manufacturing method of claim 5, wherein the thickness of the high resistance layer is the same as the thickness of the second distributed Bragg reflector along the stacking direction of the first distributed Bragg reflector and the second distributed Bragg reflector. The thickness of the distributed Bragg reflector is the same.
5. The preparation method of claim 5, wherein the high resistance layer is formed by a chemical vapor deposition method.
A camera module comprising the vertical cavity surface emitting laser according to any one of claims 1 to 4.