CN118554259A - A surface emitting laser based on femtosecond laser and its preparation method - Google Patents

Abstract

The present application relates to the technical field of laser preparation, and provides a surface emitting laser based on a femtosecond laser and a preparation method thereof. The preparation method comprises: growing a multilayer structure on a substrate; cleaning the surface of the multilayer structure on the side away from the substrate; using a femtosecond laser to prepare a plurality of long holes in the gain layer and/or the second confinement layer to form a photonic crystal structure; performing an ultrasonic cleaning treatment; depositing a patterned first metal electrode on the second confinement layer; performing annealing or photoactivation treatment; and depositing a second metal electrode on the substrate to obtain a surface emitting laser. The preparation method directly forms a photonic crystal structure on the surface or inside of the structural layer, and does not require the preparation of a mask structure, which greatly simplifies the processing technology, saves production time, reduces production costs, improves processing consistency and reliability, and can effectively achieve high-precision and low thermal effect processing.

Description

A surface emitting laser based on femtosecond laser and its preparation method

Technical Field

The present application relates to the technical field of laser preparation, and in particular to a surface emitting laser based on a femtosecond laser and a preparation method thereof.

Background Art

Photonic Crystal Surface-Emitting Laser (PCSEL) is a new type of laser that combines the advantages of photonic crystals and traditional surface-emitting lasers. Photonic crystal is a material with a periodic structure. Through periodic changes in the refractive index, the propagation path and frequency of light can be controlled. Introducing the photonic crystal structure into the surface-emitting laser can significantly improve its beam quality, enhance the directionality of its emitted light, and achieve low threshold current and high-efficiency laser emission. Although the traditional PCSEL preparation method has made significant progress, there are still some problems and challenges: the traditional lithography and etching processes are complex, with many steps and require precise control, which increases the manufacturing cost and time. The periodicity and size of the photonic crystal structure require nanometer-level precision, and a slight deviation may lead to a decrease in device performance. During the etching and epitaxial growth process, thermal effects may cause material stress and lattice defects, affecting the performance and reliability of the device. In large-scale production, it is a huge challenge to maintain the consistency of the structure and performance of each PCSEL device.

Therefore, there is an urgent need for a preparation method that can meet the structural and performance consistency of PCSEL devices.

Summary of the invention

The present application provides a femtosecond laser-based surface emitting laser and a preparation method thereof, so as to solve the technical problem that the structure and performance of a PCSEL device cannot meet the consistency requirements during the preparation process.

The first aspect of the present application provides a method for preparing a surface emitting laser based on a femtosecond laser, comprising: growing a multilayer structure on a GaAs substrate; wherein the multilayer structure comprises a buffer layer, a first confinement layer, a gain layer, and a second confinement layer grown in sequence; cleaning the surface of the multilayer structure away from the GaAs substrate; using a femtosecond laser to prepare a plurality of long holes in the gain layer and/or the second confinement layer to form a photonic crystal structure; wherein the number of long holes in the first region is less than the number of long holes in the second region, the first region is the central region of the second confinement layer and/or the gain layer, and the second region is the region of the second confinement layer and/or the gain layer other than the first region; performing an ultrasonic cleaning treatment; depositing a patterned first metal electrode on the second confinement layer; performing an annealing or photoactivation treatment; and depositing a second metal electrode on the GaAs substrate to obtain a surface emitting laser.

In some feasible implementations, a femtosecond laser is used to prepare a plurality of long holes in the gain layer and/or the second restriction layer, including: preparing a plurality of long holes on a first surface of the second restriction layer; wherein the first surface is a surface of the second restriction layer on a side away from the gain layer, and the long holes extend along the first surface toward the middle of the second restriction layer.

In some feasible implementations, a femtosecond laser is used to prepare a plurality of long holes in the gain layer and/or the second restriction layer, including: preparing a plurality of long holes in the region where the second restriction layer and the gain layer are connected; wherein the long holes extend along the second restriction layer into the gain layer, and the central axis of the long holes is parallel to the central axis of the multilayer structure; a first distance is set between the center of the long hole and the first surface, and a second distance is set between the center of the long hole and the second surface, the first surface is a surface of the second restriction layer on a side facing away from the gain layer, and the second surface is a surface of the gain layer on a side facing away from the second restriction layer.

In some feasible implementations, a femtosecond laser is used to prepare a plurality of long holes in the gain layer and/or the second restriction layer, including: preparing a plurality of long holes on the second surface of the gain layer; wherein the second surface is a surface of the gain layer on a side away from the second restriction layer, and the long holes extend along the second surface toward the middle of the gain layer.

The first aspect of the present application provides a method for preparing a surface emitting laser based on a femtosecond laser, which directly forms a photonic crystal structure on the surface or inside of a structural layer without the need to prepare a mask structure. This greatly simplifies the processing technology, saves production time, reduces production costs, improves processing consistency and reliability, and can effectively achieve high-precision and low thermal effect processing.

The surface emitting laser based on femtosecond laser provided in the second aspect of the present application is prepared by adopting the preparation method of the surface emitting laser based on femtosecond laser provided in the first aspect, and the surface emitting laser based on femtosecond laser comprises: a GaAs substrate; a multilayer structure grown on the GaAs substrate; wherein the multilayer structure comprises a buffer layer, a first confinement layer, a gain layer and a second confinement layer grown in sequence; a photonic crystal structure arranged in the gain layer and/or the second confinement layer; wherein the photonic crystal structure comprises a plurality of long holes, the number of the long holes in the first region is less than the number of the long holes in the second region, the first region is the central region of the second confinement layer and/or the gain layer, and the second region is the region of the second confinement layer and/or the gain layer other than the first region; a patterned first metal electrode deposited in the second confinement layer; and a second metal electrode deposited on the GaAs substrate.

The femtosecond laser-based surface emitting laser provided in the second aspect of the present application is prepared by the preparation method provided in the first aspect. Its beneficial technical effects can be found in the first aspect and will not be described in detail here.

The third aspect of the present application provides a method for preparing a surface emitting laser based on a femtosecond laser, comprising: growing a multilayer structure on a GaAs substrate; wherein the multilayer structure comprises a buffer layer, a first confinement layer, a gain layer, and a second confinement layer grown in sequence; growing a silicon oxide layer on the multilayer structure; cleaning the surface of the silicon oxide layer on a side away from the multilayer structure; using a femtosecond laser to prepare a plurality of long holes in the silicon oxide layer to form a photonic crystal structure; wherein the number of long holes in a first region is less than the number of long holes in a second region, the first region is the central region of the silicon oxide layer, and the second region is the region of the silicon oxide layer other than the first region; performing an ultrasonic cleaning treatment; depositing a patterned first metal electrode on the silicon oxide layer; performing an annealing or photoactivation treatment; and depositing a second metal electrode on the GaAs substrate to obtain a surface emitting laser.

In some feasible implementations, a femtosecond laser is used to prepare multiple long holes in the silicon oxide layer to form a photonic crystal structure, including: preparing multiple long holes on the third surface of the silicon oxide layer; wherein the third surface is the surface of the silicon oxide layer away from the multilayer structure, and the long holes extend along the third surface toward the middle of the silicon oxide layer.

In some feasible implementations, a femtosecond laser is used to prepare multiple long holes in a silicon oxide layer to form a photonic crystal structure, including: preparing multiple long holes in the middle of the silicon oxide layer; wherein a third distance is set between the center of the long hole and the third surface, and a fourth distance is set between the center of the long hole and the fourth surface, the third surface is the surface of the silicon oxide layer facing away from the multilayer structure, the fourth surface is the connecting surface between the silicon oxide layer and the multilayer structure, and the central axis of the long hole is parallel to the central axis of the silicon oxide layer.

In some feasible implementations, a femtosecond laser is used to prepare multiple long holes in the silicon oxide layer to form a photonic crystal structure, including: preparing multiple long holes on the fourth surface of the silicon oxide layer; wherein the fourth surface is the connecting surface between the silicon oxide layer and the multilayer structure, and the long holes extend along the fourth surface toward the middle of the silicon oxide layer.

The third aspect of the present application provides a method for preparing a surface emitting laser based on a femtosecond laser, which directly forms a photonic crystal structure on the surface or inside of a structural layer without the need to prepare a mask structure. This greatly simplifies the processing technology, saves production time, reduces production costs, improves processing consistency and reliability, and can effectively achieve high-precision and low thermal effect processing.

The surface emitting laser based on femtosecond laser provided in the fourth aspect of the present application is prepared by the preparation method provided in the third aspect, and the surface emitting laser based on femtosecond laser includes a GaAs substrate; a multilayer structure, grown on the GaAs substrate; wherein the multilayer structure includes a buffer layer, a first confinement layer, a gain layer and a second confinement layer grown in sequence; a silicon oxide layer, grown on the multilayer structure; a photonic crystal structure, arranged in the silicon oxide layer; wherein the photonic crystal structure includes a plurality of long holes, the number of long holes in the first region is less than the number of long holes in the second region, the first region is the central region of the silicon oxide layer, and the second region is the region of the silicon oxide layer other than the first region; a patterned first metal electrode, deposited on the silicon oxide layer; and a second metal electrode, deposited on the GaAs substrate.

The surface emitting laser based on femtosecond laser provided in the fourth aspect of the present application is prepared by the preparation method provided in the third aspect. The beneficial technical effects thereof can be found in the third aspect and will not be described in detail here.

BRIEF DESCRIPTION OF THE DRAWINGS

In order to more clearly illustrate the technical solution of the present application, the drawings required for use in the embodiments are briefly introduced below. Obviously, for ordinary technicians in this field, other drawings can be obtained based on these drawings without any creative work.

FIG1 is a schematic flow chart of a method for preparing a surface laser based on femtosecond laser processing provided in an embodiment of the present application;

FIG2 is a schematic diagram of a multilayer structure provided in an embodiment of the present application;

FIG3 is a schematic diagram of a first structure of a long hole provided in an embodiment of the present application;

FIG4 is a schematic diagram of a second structure of a long hole provided in an embodiment of the present application;

FIG5 is a schematic diagram of a third structure of a long hole provided in an embodiment of the present application;

FIG6 is a schematic diagram of a fourth structure of a long hole provided in an embodiment of the present application;

FIG7 is a schematic diagram of a fifth structure of a long hole provided in an embodiment of the present application;

FIG8 is a sixth structural schematic diagram of a long hole provided in an embodiment of the present application;

FIG9 is a seventh structural schematic diagram of a long hole provided in an embodiment of the present application;

FIG10 is a top view of a multilayer structure provided in an embodiment of the present application;

FIG11 is a schematic structural diagram of a surface emitting laser provided in an embodiment of the present application;

12 is a schematic flow chart of another method for preparing a surface laser based on femtosecond laser processing provided in an embodiment of the present application;

FIG13 is a schematic diagram of the structure of a silicon oxide layer provided in an embodiment of the present application;

FIG14 is a schematic diagram of an eighth structure of a long hole provided in an embodiment of the present application;

FIG15 is a schematic diagram of a ninth structure of a long hole provided in an embodiment of the present application;

FIG16 is a schematic diagram of the tenth structure of the long hole provided in an embodiment of the present application;

FIG. 17 is a schematic diagram of the structure of another surface emitting laser provided in an embodiment of the present application.

Graphic marking:

1-GaAs substrate; 2-multilayer structure; 21-buffer layer; 22-first confinement layer; 23-gain layer; 231-second surface; 24-second confinement layer; 241-first surface; 3-long hole; 4-first metal electrode; 5-second metal electrode; 6-silicon oxide layer; 61-third surface; 62-fourth surface.

DETAILED DESCRIPTION

The technical solutions in the embodiments of the present application will be described clearly below in conjunction with the drawings in the embodiments of the present application. Obviously, the described embodiments are part of the embodiments of the present application, rather than all of the embodiments. Based on the embodiments of the present application, other embodiments obtained by ordinary technicians in this field without making creative work all belong to the protection scope of the present application.

In the following, the terms "first", "second", etc. are used for descriptive purposes only and are not to be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Thus, a feature defined as "first", "second", etc. may explicitly or implicitly include one or more of the feature. In the description of this application, unless otherwise specified, "plurality" means two or more.

In addition, in the present application, directional terms such as "upper", "lower", "inner" and "outer" are defined relative to the orientation of the components in the drawings. It should be understood that these directional terms are relative concepts. They are used for relative description and clarification, and they can change accordingly according to the changes in the orientation of the components in the drawings.

In order to solve the technical problem that the structure and performance cannot meet the consistency requirements during the laser preparation process, the embodiment of the present application provides a method for preparing a surface emitting laser based on a femtosecond laser.

1 and 2 , the method for preparing a surface emitting laser based on a femtosecond laser provided in an embodiment of the present application can be implemented by the following steps S100 to S700 .

Step S100 : growing a multilayer structure 2 on a GaAs substrate 1 .

In step S100 , the multilayer structure 2 may be prepared by molecular beam epitaxy (MBE) or metal-organic chemical vapor deposition (MOCVD); wherein the multilayer structure 2 includes a buffer layer 21 , a first confinement layer 22 , a gain layer 23 and a second confinement layer 24 grown in sequence.

In a specific implementation, the gain layer 23 may be an InGaAs/GaAs quantum well.

Step S200 : cleaning the surface of the multilayer structure 2 facing away from the GaAs substrate 1 .

The surface of the multilayer structure 2 can be cleaned in sequence using isopropyl ketone and deionized water, wherein the isopropyl ketone can be analytical grade, and the cleaning operation can be performed at room temperature and pressure.

After executing step S200, the structure shown in FIG. 2 can be obtained.

Step S300: using a femtosecond laser to prepare a plurality of long holes in the gain layer 23 and/or the second confinement layer 24 to form a photonic crystal structure.

In step S300 , the photonic crystal structure may be prepared on the gain layer 23 , the photonic crystal structure may be prepared on the second confinement layer 24 , or the photonic crystal structure may be prepared on both the gain layer 23 and the second confinement layer 24 .

In a specific implementation, referring to FIG. 3 , step S300 may be implemented by the following step S301 .

Step S301 : preparing a plurality of long holes 3 on the first surface 241 of the second restriction layer 24 .

Specifically, in this implementation, a plurality of long holes 3 are prepared on the upper portion of the second restriction layer 24. The long holes 3 extend along the first surface 241 toward the middle of the second restriction layer 24. In other words, the central axis of the long hole 3 is parallel to the central axis of the multilayer structure 2. The first surface 241 is the surface of the second restriction layer 24 that is away from the gain layer 23.

In a specific implementation, referring to FIG. 4 , step S300 may be implemented by the following step S302 .

Step S302 : preparing a plurality of long holes 3 in the middle of the second restriction layer 24 .

Specifically, in this implementation, the long hole 3 extends inside the second restriction layer 24, and the straight line in the extension direction is parallel to the central axis of the second restriction layer 24. In other words, the central axis of the long hole 3 is parallel to the central axis of the multilayer structure 2.

In a specific implementation, referring to FIG. 5 , step S300 may be implemented by the following step S303 .

Step S303 : preparing a plurality of long holes 3 at the lower portion of the second restriction layer 24 .

Specifically, in this implementation, the long hole 3 extends toward the middle of the second restriction layer 24 along the connecting surface between the second restriction layer 24 and the gain layer 23. In other words, the central axis of the long hole 3 is parallel to the central axis of the multilayer structure 2.

In a specific implementation, referring to FIG. 6 , step S300 may be implemented by the following step S304 .

Step S304: preparing a plurality of long holes 3 in the region where the second limiting layer 24 and the gain layer 23 are connected.

Specifically, in this implementation, the long hole 3 extends along the second restriction layer 24 into the gain layer 23, and the central axis of the long hole 3 is parallel to the central axis of the multilayer structure 2; a first distance D1 is set between the center of the long hole 3 and the first surface 241, and a second distance D2 is set between the center of the long hole 3 and the second surface 231. The first surface 241 is the surface of the second restriction layer 24 on the side away from the gain layer 23, and the second surface 231 is the surface of the gain layer 23 on the side away from the second restriction layer 24.

The first distance D1 and the second distance D2 may be the same or different. That is, in this implementation, the center of the long hole 3 may be located on the connecting surface of the second restriction layer 24 and the gain layer 23, or in the second restriction layer 24, or in the gain layer 23.

In a specific implementation, referring to FIG. 7 , step S300 may be implemented by the following step S305 .

Step S305 : preparing a plurality of long holes 3 on the upper portion of the gain layer 23 .

Specifically, in this implementation, the long hole 3 extends toward the middle of the gain layer 23 along the connecting surface between the second restriction layer 24 and the gain layer 23 , and the central axis of the long hole 3 is parallel to the central axis of the gain layer 23 .

In a specific implementation, referring to FIG. 8 , step S300 may be implemented by the following step S306 .

Step S306 : preparing a plurality of long holes 3 in the middle of the gain layer 23 .

Specifically, in this implementation, the long hole 3 is located inside the gain layer 23 , and the central axis of the long hole 3 is parallel to the central axis of the gain layer 23 .

In a specific implementation, referring to FIG. 9 , step S300 may be implemented by the following step S307 .

Step S307 : preparing a plurality of long holes 3 on the second surface 231 of the gain layer 23 .

Specifically, in this implementation, the long hole 3 extends along the second surface 231 toward the middle of the gain layer 23 . The second surface 231 is the surface of the gain layer 23 that is away from the second restriction layer 24 .

It should be emphasized that when actually preparing a surface emitting laser, any one of the preparation methods in steps S301 to S307 can be selected. That is, the position of the long hole 3 is determined according to the performance of the photonic crystal structure to be prepared, and then the corresponding preparation method is selected.

Specifically, in the above steps S301 to S307, a femtosecond laser with a wavelength of 808nm, a pulse width of 50 femtoseconds, a repetition frequency of 5kHz, and a laser energy of 10mJ can be used to prepare a photonic crystal structure that meets the requirements of a photonic crystal laser (PCSEL). Femtosecond lasers have ultra-short pulse widths and high peak power, and can achieve high-precision and low-heat-effect processing. This technology can form a photonic crystal structure directly on the surface or inside of a material without introducing significant thermal effects, which simplifies the processing technology, saves production time, reduces production costs, and improves the consistency and reliability of processing.

The multiple long holes 3 formed are of a periodic structure, the diameter of the long holes 3 may be 10 nm-1 μm, the period may be 100 nm-2 μm, and the hole depth is less than 5 μm. The period refers to the distance between the centers of two adjacent long holes 3 .

During the preparation process, a high-precision three-axis motion platform can be used to ensure that the prepared sample is firmly fixed and accurately positioned, and the processed substrate is fixed on the platform to ensure that there is no looseness. According to the specific position of the long hole 3 to be prepared, the scanning path of the femtosecond laser is set, and the femtosecond laser is controlled to scan the prepared sample along the scanning path to form a periodic photonic crystal structure. During the preparation process, an optical microscope or an online interferometer can be used to monitor the processing process in real time to ensure the processing accuracy.

In the above steps S301 to S307, in order not to affect the light extraction efficiency of the surface emitting laser, the number of the long holes 3 is reduced in the light extraction area.

10 , the first region a is the light emitting region of the surface emitting laser, that is, from a top view, the central region of the multilayer structure 2 is the light emitting region. The number of the long holes 3 in the first region a is less than the number of the long holes 3 in the second region b, and the second region b is the region of the second confinement layer 24 and/or the gain layer 23 except the first region a.

Specifically, when preparing the photonic crystal structure, the geometric size and shape of the resonant cavity can be designed according to the design requirements of the surface emitting laser, and then the resonant cavity structure is formed on the prepared sample by a femtosecond laser.

Step S400: performing ultrasonic cleaning.

Ultrasonic cleaning can be used to remove the processing residues on the wall surface of the long hole 3.

Specifically, if the long hole 3 is prepared by step S301, after step S400 is completed, there is no processing residue inside the long hole 3. If the other preparation methods except step S301 are adopted, since the long hole 3 prepared by these preparation methods is a closed hole structure that is not connected to the outside, after step S400 is completed, the residue on the wall of the long hole 3 will be deposited at the bottom of the long hole 3, which plays a role in cleaning the wall of the long hole 3.

1 and 11 , step S500 : depositing a patterned first metal electrode 4 on the second restriction layer 24 .

Specifically, step S500 can be implemented by steps S501 to S503.

Step S501 : depositing a first metal electrode 4 on the second restriction layer 24 .

The first metal electrode 4 may be prepared by electron beam evaporation technology or sputtering.

Step S502 : preparing a patterned mask layer on the first metal electrode 4 .

A patterned mask layer (not shown in the figure) may be prepared by using photolithography technology.

Step S503: stripping off the first metal electrode 4 outside the patterned mask layer, and removing the patterned mask layer.

Specifically, the shape of the patterned mask layer can be the same as the shape of the patterned first metal electrode 4 to be prepared, so that the remaining portion is peeled off by a peeling technique to obtain the patterned first metal electrode 4.

The shape of the patterned first metal electrode 4 can be any shape as long as it can meet the use function of the first metal electrode 4. The projection of the patterned first metal electrode 4 toward the GaAs substrate 1 covers part of the long hole 3.

In a specific implementation, the shape of the patterned first metal electrode 4 is ring-shaped.

Step S600: performing annealing or photoactivation treatment.

In step S600, the gain material is activated by annealing or photo-activation.

1 and 11 , step S700 : depositing a second metal electrode 5 on the GaAs substrate 1 to obtain a surface emitting laser.

The second metal electrode 5 may be prepared by electron beam evaporation technology or sputtering.

It should be emphasized that FIG11 is only one of the surface emitting lasers, in which the plurality of long holes 3 are located at the lower position of the gain layer 23. In the other surface emitting lasers, the long holes 3 may also be located at the positions shown in FIG3 to FIG8.

The method for preparing a surface emitting laser based on a femtosecond laser provided in the embodiment of the present application directly forms a photonic crystal structure on the surface or inside of a structural layer without the need to prepare a mask structure. This greatly simplifies the processing technology, saves production time, reduces production costs, improves processing consistency and reliability, and can effectively achieve high-precision and low thermal effect processing.

Corresponding to the aforementioned embodiment of a method for preparing a surface emitting laser based on a femtosecond laser, the present application also provides an embodiment of a surface emitting laser based on a femtosecond laser.

Continuing with FIG. 10 and FIG. 11 , the surface emitting laser based on a femtosecond laser provided in the embodiment of the present application includes a GaAs substrate 1 , a multilayer structure 2 , a photonic crystal structure, a patterned first metal electrode 4 and a second metal electrode 5 .

The multilayer structure 2 is grown on the GaAs substrate 1; wherein the multilayer structure 2 includes a buffer layer 21, a first confinement layer 22, a gain layer 23 and a second confinement layer 24 which are grown in sequence.

Specifically, the multilayer structure 2 can be prepared by step S100 in the above-mentioned method for preparing a surface emitting laser based on a femtosecond laser.

A photonic crystal structure is arranged in the gain layer 23 and/or the second limiting layer 24; wherein the photonic crystal structure includes a plurality of long holes 3, the number of the long holes 3 in the first region is less than the number of the long holes 3 in the second region, the first region a is the central region of the second limiting layer 24 and/or the gain layer 23, and the second region b is the region of the second limiting layer 24 and/or the gain layer 23 except the first region a.

Specifically, the photonic crystal structure can be prepared by step S300 in the above-mentioned method for preparing a surface emitting laser based on a femtosecond laser.

In this implementation, the photonic crystal structure is disposed in the gain layer 23 . In other specific implementations, the photonic crystal structure may also be disposed in the second confinement layer 24 or in the gain layer 23 and the second confinement layer 24 .

The patterned first metal electrode 4 is deposited on the second confinement layer 24. Specifically, the patterned first metal electrode 4 can be prepared by step S500 in the above-mentioned method for preparing a surface emitting laser based on a femtosecond laser.

The second metal electrode 5 is deposited on the GaAs substrate 1. Specifically, the second metal electrode 5 can be prepared by step S700 in the above-mentioned method for preparing a surface emitting laser based on a femtosecond laser.

12 and 13 , the present application also provides another method for preparing a surface emitting laser based on a femtosecond laser. The preparation method can be implemented by the following steps A100 to A800 .

A100: growing a multilayer structure 2 on a GaAs substrate 1; wherein the multilayer structure 2 comprises a buffer layer 21, a first confinement layer 22, a gain layer 23 and a second confinement layer 24 grown in sequence.

In this embodiment, step A100 may adopt the same preparation process as step S100 of the preparation method in the above-mentioned embodiment.

A200 : growing a silicon oxide layer 6 on the multilayer structure 2 .

The silicon oxide layer 6 may be formed on the surface of the multilayer structure 2 facing away from the GaAs substrate 1 by using a plasma enhanced chemical vapor deposition (PECVD) technique.

A300: Cleaning the surface of the silicon oxide layer 6 facing away from the multilayer structure 2 .

In this embodiment, step A300 may adopt the same preparation process as step S200 of the preparation method in the above-mentioned embodiment.

A400: A femtosecond laser is used to prepare multiple long holes in the silicon oxide layer 6 to form a photonic crystal structure; wherein the number of long holes in the first area is less than the number of long holes in the second area, the first area is the central area of the silicon oxide layer 6, and the second area is the area in the silicon oxide layer 6 except the first area.

Specifically, in step A400, a plurality of long holes are prepared in the silicon oxide layer 6. The long holes can be prepared in any one of the upper part, the middle part or the lower part of the silicon oxide layer 6.

In a specific implementation, referring to FIG. 14 , step A400 may be implemented by the following step A401 .

Step A401 : preparing a plurality of long holes 3 on the third surface 61 of the silicon oxide layer 6 .

Specifically, in this implementation, a plurality of long holes 3 are prepared on the upper part of the silicon oxide layer 6. The third surface 61 is the surface of the silicon oxide layer 6 on the side away from the multilayer structure 2, and the long holes 3 extend along the third surface 61 toward the middle of the silicon oxide layer 6, and the central axis of the long holes 3 is parallel to the central axis of the silicon oxide layer 6.

In a specific implementation, referring to FIG. 15 , step A400 may be implemented by the following step A402 .

Step A402: Prepare a plurality of long holes 3 in the middle of the silicon oxide layer 6.

Specifically, in this implementation, a plurality of long holes 3 are prepared in the middle of the silicon oxide layer 6. A third distance D3 is set between the center of the long hole 3 and the third surface 61, a fourth distance D4 is set between the center of the long hole 3 and the fourth surface 62, the third surface 61 is the surface of the silicon oxide layer 6 facing away from the multilayer structure 2, the fourth surface 62 is the connection surface between the silicon oxide layer 6 and the multilayer structure 2, and the central axis of the long hole 3 is parallel to the central axis of the silicon oxide layer 6.

The third distance D3 and the fourth distance D4 may be the same or different.

In a specific implementation, referring to FIG. 16 , step A400 may be implemented by the following step A403 .

Step A403 : preparing a plurality of long holes 3 on the fourth surface 62 of the silicon oxide layer 6 .

Specifically, in this implementation, a plurality of long holes 3 are prepared at the bottom of the silicon oxide layer 6 . The fourth surface 62 is the connection surface between the silicon oxide layer 6 and the multilayer structure 2 , and the long holes 3 extend toward the middle of the silicon oxide layer 6 along the fourth surface 62 .

In step A401 to step A403, the preparation process and parameters of the long hole 3 may be the same as step S301 to step S307 in the above-mentioned preparation method embodiment.

Step A500: Perform ultrasonic cleaning.

In this embodiment, step A500 may adopt the same preparation process as step S400 of the preparation method in the above-mentioned embodiment.

12 and 17 , step A600 : depositing a patterned first metal electrode 4 on the silicon oxide layer 6 .

In this embodiment, step A600 may adopt the same preparation process as step S500 of the preparation method in the above embodiment. The difference from step S500 is that in step A600, the first metal electrode 4 is deposited on the silicon oxide layer 6.

Step A700: performing annealing or photoactivation treatment.

In this embodiment, step A700 may adopt the same preparation process as step S600 of the preparation method in the above-mentioned embodiment.

12 and 17 , step A800 : depositing a second metal electrode 5 on the GaAs substrate 1 to obtain a surface emitting laser.

In this embodiment, step A800 may adopt the same preparation process as step S700 of the preparation method in the above-mentioned embodiment.

It should be emphasized that the preparation method provided in this embodiment is different from the preparation method provided in the previous embodiment in that a silicon oxide layer 6 is also required to be prepared in this embodiment, and the photonic crystal structure is prepared in the silicon oxide layer 6, and the preparation process and parameters used in the remaining steps can be the same as those provided in the previous embodiment.

Similar to the preparation method provided in the aforementioned embodiment, this preparation method directly forms a photonic crystal structure on the surface or inside of the structural layer, and does not require the preparation of a mask structure. This greatly simplifies the processing technology, saves production time, reduces production costs, improves processing consistency and reliability, and can effectively achieve high-precision and low thermal effect processing.

Continuing to refer to FIG. 17 , corresponding to the embodiment of the preparation method, the present application also provides an embodiment of a surface emitting laser based on a femtosecond laser.

The surface emitting laser includes a GaAs substrate 1 , a multilayer structure 2 , a silicon oxide layer 6 , a photonic crystal structure, a first metal electrode 4 and a second metal electrode 5 .

The multilayer structure 2 is grown on the GaAs substrate 1; wherein the multilayer structure 2 includes a buffer layer 21, a first confinement layer 22, a gain layer 23 and a second confinement layer 24 which are grown in sequence.

Specifically, the multilayer structure 2 can be prepared by step A100 in the above-mentioned preparation method embodiment.

A silicon oxide layer 6 is grown on the multilayer structure 2 .

Specifically, the silicon oxide layer 6 can be prepared by step A200 in the above-mentioned preparation method embodiment.

A photonic crystal structure is arranged in the silicon oxide layer 6; wherein the photonic crystal structure includes a plurality of long holes 3, the number of the long holes 3 in the first region is less than the number of the long holes 3 in the second region, the first region is the central region of the silicon oxide layer 6, and the second region is the region of the silicon oxide layer 6 excluding the first region.

Specifically, the photonic crystal structure can be prepared by step A400 in the above-mentioned preparation method embodiment.

The patterned first metal electrode 4 is deposited on the silicon oxide layer 6 .

Specifically, the patterned first metal electrode 4 can be prepared by step A600 in the above-mentioned preparation method embodiment.

The second metal electrode 5 is deposited on the GaAs substrate 1 .

Specifically, the second metal electrode 5 can be prepared by step A800 in the above-mentioned preparation method embodiment.

It is worth noting that the multiple long holes 3 in FIG. 17 are arranged at the lower position of the silicon oxide layer 6 , and in other specific implementations, the multiple long holes 3 may also be arranged in the middle or upper part of the silicon oxide layer 6 .

It should be noted that those skilled in the art will easily think of other embodiments of the present application after considering the specification and practicing the application disclosed herein. The present application is intended to cover any variation, use or adaptation of the present application, which follows the general principles of the present application and includes common knowledge or customary technical means in the art that are not disclosed in the present application.

It should be understood that the present application is not limited to the precise construction that has been described above and shown in the drawings, and that various modifications and changes may be made without departing from the scope thereof, the true scope being indicated by the present application.

Claims (10)

1. A method for preparing a surface emitting laser based on femtosecond laser, comprising:

Growing a multilayer structure on a GaAs substrate; the multi-layer structure comprises a buffer layer, a first limiting layer, a gain layer and a second limiting layer which are sequentially grown;

cleaning the surface of the side, facing away from the GaAs substrate, of the multilayer structure;

Preparing a plurality of long holes in the gain layer and/or the second limiting layer by using femtosecond laser so as to form a photonic crystal structure; the number of the long holes in a first area is smaller than that of the long holes in a second area, the first area is a central area of the second limiting layer and/or the gain layer, and the second area is an area, except the first area, of the second limiting layer and/or the gain layer;

performing ultrasonic cleaning treatment;

depositing a patterned first metal electrode on the second confinement layer;

Annealing or photo-activating treatment is carried out;

And depositing a second metal electrode on the GaAs substrate to obtain the surface-emitting laser.

2. The method for manufacturing a femtosecond laser-based surface emitting laser according to claim 1,

The preparing a plurality of long holes on the gain layer and/or the second limiting layer by using the femtosecond laser comprises the following steps:

Preparing a plurality of long holes on the first surface of the second limiting layer; the first surface is a surface of the second limiting layer, which faces away from one side of the gain layer, and the long hole extends along the first surface to the middle of the second limiting layer.

3. The method for manufacturing a femtosecond laser-based surface emitting laser according to claim 1,

The preparing a plurality of long holes on the gain layer and/or the second limiting layer by using the femtosecond laser comprises the following steps:

Preparing a plurality of long holes in the area where the second limiting layer is connected with the gain layer; the long holes extend into the gain layer along the second limiting layer, and the central axes of the long holes are parallel to the central axes of the multilayer structure; the center of the long hole is provided with a first distance from the first surface, the center of the long hole is provided with a second distance from the second surface, the first surface is the surface of the second limiting layer, which is away from one side of the gain layer, and the second surface is the surface of the gain layer, which is away from one side of the second limiting layer.

4. The method for manufacturing a femtosecond laser-based surface emitting laser according to claim 1,

The preparing a plurality of long holes on the gain layer and/or the second limiting layer by using the femtosecond laser comprises the following steps:

Preparing a plurality of long holes on the second surface of the gain layer; the second surface is a surface of the gain layer, which faces away from one side of the second limiting layer, and the long hole extends along the second surface towards the middle of the gain layer.

5. A surface emitting laser based on femtosecond laser, wherein the surface emitting laser based on femtosecond laser is prepared by the preparation method of the surface emitting laser based on femtosecond laser according to any one of claims 1 to 4, and the surface emitting laser based on femtosecond laser comprises:

a GaAs substrate;

a multi-layer structure grown on the GaAs substrate; the multi-layer structure comprises a buffer layer, a first limiting layer, a gain layer and a second limiting layer which are sequentially grown;

The photonic crystal structure is arranged on the gain layer and/or the second limiting layer; the photonic crystal structure comprises a plurality of long holes, the number of the long holes in a first area is smaller than that of the long holes in a second area, the first area is a central area of the second limiting layer and/or the gain layer, and the second area is an area of the second limiting layer and/or the gain layer except the first area;

a patterned first metal electrode deposited on the second confinement layer;

And a second metal electrode deposited on the GaAs substrate.

6. A method for preparing a surface emitting laser based on femtosecond laser, comprising:

Growing a multilayer structure on a GaAs substrate; the multi-layer structure comprises a buffer layer, a first limiting layer, a gain layer and a second limiting layer which are sequentially grown;

Growing a silicon oxide layer on the multilayer structure;

Cleaning the surface of the silicon oxide layer on the side away from the multilayer structure;

preparing a plurality of long holes in the silicon oxide layer by using femtosecond laser so as to form a photonic crystal structure; the number of the long holes in a first area is smaller than that of the long holes in a second area, the first area is a central area of the silicon oxide layer, and the second area is an area of the silicon oxide layer except the first area;

performing ultrasonic cleaning treatment;

Depositing a patterned first metal electrode on the silicon oxide layer;

Annealing or photo-activating treatment is carried out;

And depositing a second metal electrode on the GaAs substrate to obtain the surface-emitting laser.

7. The method for manufacturing a femtosecond laser based surface emitting laser according to claim 6,

The preparing a plurality of long holes on the silicon oxide layer by using femtosecond laser to form a photonic crystal structure comprises the following steps:

Preparing a plurality of long holes on the third surface of the silicon oxide layer; the third surface is a surface of the silicon oxide layer, which is away from one side of the multilayer structure, and the long holes extend along the third surface towards the middle of the silicon oxide layer.

8. The method for manufacturing a femtosecond laser based surface emitting laser according to claim 6,

The preparing a plurality of long holes on the silicon oxide layer by using femtosecond laser to form a photonic crystal structure comprises the following steps:

Preparing a plurality of long holes in the middle of the silicon oxide layer; the center of the long hole is provided with a third distance from a third surface, the center of the long hole is provided with a fourth distance from a fourth surface, the third surface is a surface of the silicon oxide layer, which is away from one side of the multilayer structure, the fourth surface is a connecting surface of the silicon oxide layer and the multilayer structure, and the central axis of the long hole is parallel to the central axis of the silicon oxide layer.

9. The method for manufacturing a femtosecond laser based surface emitting laser according to claim 6,

The preparing a plurality of long holes on the silicon oxide layer by using femtosecond laser to form a photonic crystal structure comprises the following steps:

Preparing a plurality of long holes on the fourth surface of the silicon oxide layer; the fourth surface is a connection surface between the silicon oxide layer and the multilayer structure, and the long holes extend along the fourth surface towards the middle of the silicon oxide layer.

10. A surface emitting laser based on femtosecond laser, wherein the surface emitting laser based on femtosecond laser is prepared by a preparation method of the surface emitting laser based on femtosecond laser as set forth in any one of claims 6 to 9, and the surface emitting laser based on femtosecond laser includes:

a GaAs substrate;

a multi-layer structure grown on the GaAs substrate; the multi-layer structure comprises a buffer layer, a first limiting layer, a gain layer and a second limiting layer which are sequentially grown;

a silicon oxide layer grown on the multilayer structure;

The photonic crystal structure is arranged on the silicon oxide layer; the photonic crystal structure comprises a plurality of long holes, the number of the long holes in a first area is smaller than that of the long holes in a second area, the first area is a central area of the silicon oxide layer, and the second area is an area of the silicon oxide layer except the first area;

a patterned first metal electrode deposited on the silicon oxide layer;

And a second metal electrode deposited on the GaAs substrate.