CN115207771A - VCSEL device integrated at wafer level and preparation method of VCSEL device - Google Patents

Abstract

A VCSEL device integrated at the wafer level and a preparation method of the VCSEL device are disclosed. Wherein, the VCSEL device integrates a VCSEL laser and an optical element for modulating the laser light emitted by the VCSEL laser at the wafer level. During the manufacturing process of the VCSEL device, relatively precise positioning is achieved at the wafer level between the VCSEL laser and the optical element, so that there is a space between the VCSEL laser and the optical element in the final molded VCSEL device. Relatively high positioning accuracy.

Description

VCSEL devices integrated at wafer level and methods of making VCSEL devices

technical field

The present invention relates to the field of semiconductors, and more particularly to a VCSEL device integrated at the wafer level and a method for preparing the VCSEL device.

Background technique

Vertical-Cavity Surface-Emitting Laser (VCSEL) is a semiconductor laser whose laser is emitted perpendicular to the upper or lower surface. Compared with traditional edge-emitting semiconductor lasers, VCSEL lasers have the characteristics of small temperature drift, low threshold, high fiber coupling efficiency, and easy integration and packaging.

In practical industries, VCSEL lasers are often used as basic components (eg, as a light source) and other devices assembled into modules. For example, when a VCSEL laser is applied to a TOF camera module, the VCSEL laser is assembled with circuit boards, brackets, optical diffraction elements, metal shields and other devices to form a laser projection module for the TOF camera module.

When assembling the VCSEL laser and other devices to form a projection module, an important technical challenge is how to stably and accurately install the optical element for modulating the laser light on the laser projection path of the VCSEL laser. For example, during the assembly process of the laser projection module of the TOF camera module as described above, the installation accuracy of the optical diffraction element relative to the VCSEL laser will greatly affect the performance of the laser projection module.

In the existing VCSEL laser package products, the relative positional relationship between the VCSEL laser and the optical components is achieved by physical positioning and/or structural cooperation. For example, in the above-mentioned laser projection module of the TOF camera module, the relative positional relationship between the optical diffraction element and the VCSEL laser depends on the installation accuracy of the bracket mounted on the circuit board and the installation of the optical diffraction element on the bracket. accuracy to ensure. However, this technical solution relying on physical positioning and/or structural cooperation has many defects in practical applications.

First, the positioning accuracy that can be achieved by physical positioning is limited, that is, when the accuracy of the relative positional relationship between the VCSEL laser and the optical components is high, the physical positioning may not meet the application requirements.

Secondly, the realization of physical positioning needs to rely on a specific physical structure. Accordingly, the stability of the physical structure will affect the stability of the positioning. It should be understood that for physical structures, even if there is no accidental collision, the matching accuracy between the physical structures may decrease over time, which affects the relative positional relationship between the optical components and the VCSEL laser. .

In order to improve the stability between the VCSEL laser and the optical components, some manufacturers choose to directly mount the optical components on the laser exit surface of the VCSEL laser. Although this assembly scheme can improve the coordination stability between the VCSEL laser and optical components to a certain extent, this assembly scheme is still difficult to ensure the positioning and coordination accuracy between the VCSEL laser and the optical components, resulting in the final product formed. It is still difficult to meet the performance requirements.

In the actual industry, VCSEL lasers are usually provided by chip manufacturers, and the assembly work of VCSEL packaged products is completed by packaging factories. That is, from VCSEL lasers to VCSEL packaged products through two nodes in the industry chain. Moreover, in the actual industry, packaging factories may purchase VCSEL lasers provided by different manufacturers. At the same time, problems such as different assembly accuracy may occur during the assembly process, which makes it difficult to ensure the consistency of the final molded VCSEL packaging products.

SUMMARY OF THE INVENTION

An object of the present application is to provide a VCSEL device integrated at a wafer level and a method for fabricating a VCSEL device, wherein the VCSEL device integrates a VCSEL laser and an optical device for modulating the laser light emitted by the VCSEL laser at the wafer level element.

Another object of the present application is to provide a VCSEL device integrated at the wafer level and a method for fabricating the VCSEL device, wherein during the fabrication process of the VCSEL device, a relative relationship between the VCSEL laser and the optical element is achieved at the wafer level. The positioning is relatively precise, so that the VCSEL laser and the optical element in the final formed VCSEL device have relatively high positioning accuracy.

Yet another object of the present application is to provide a VCSEL device integrated at a wafer level and a method for fabricating a VCSEL device, wherein the VCSEL laser and the optical element are configured integrally at the wafer level, and the VCSEL laser is integrated at the wafer level. There are no other redundant components between the laser and the optical element that affect the laser so that the VCSEL device can project laser light modulated by the optical element with relatively high precision.

Another object of the present application is to provide a VCSEL device integrated at the wafer level and a method for manufacturing the VCSEL device, wherein the preparation of the VCSEL device can be completed in a chip manufacturing plant, thereby improving industrial efficiency.

Yet another object of the present application is to provide a VCSEL device integrated at the wafer level and a method for fabricating a VCSEL device, wherein, during the fabrication process, the optical element can be precisely fabricated at the wafer level through an existing semiconductor process. Shaped at the preset position of the VCSEL laser. That is, the VCSEL device can be completed based on existing mature semiconductor processes.

In order to achieve the above-mentioned at least one object of the invention, the present invention provides a VCSEL device integrated at the wafer level, which includes:

an epitaxial structure, comprising in sequence from bottom to top: a substrate, a first reflector, an active region, a confinement layer and a second reflector, wherein the confinement layer has a confinement hole corresponding to the active region;

an optical element integrally formed on the upper or lower surface of the epitaxial structure; and

Electrically connected to the positive electrode and the negative electrode of the epitaxial structure.

In the VCSEL device integrated at the wafer level according to the present application, the optical element is grown on the upper surface of the epitaxial structure by a semiconductor growth process.

In the VCSEL device integrated at the wafer level according to the present application, the optical element is made of any one of the following materials: GaN, Al _X Ga _1-X As (x=0-1), GaAs, lnP, GaN and additives, Al _X Ga _1-X As (x=0-1) and additives, GaAs and additives, lnP and additives.

In the VCSEL device integrated at the wafer level according to the present application, the optical element is a concave lens or a convex lens.

In a VCSEL device integrated at the wafer level according to the present application, the optical element is a grating.

In a VCSEL device integrated at the wafer level according to the present application, the confinement layer is an oxidation confinement layer.

In a VCSEL device integrated at the wafer level according to the present application, the confinement layer is an ion confinement layer.

According to another aspect of the present application, there is also provided a method for preparing a VCSEL device, comprising:

An epitaxial structure is formed by an epitaxial growth process, wherein the epitaxial structure includes, from bottom to top, a substrate, a first reflector, an active region, a confinement layer and a second reflector, wherein the confinement layer has a confinement hole corresponding to the active region;

A semiconductor layer to be processed is integrally formed on the surface of the epitaxial structure;

An etchable material is applied on the semiconductor layer to be processed, and the etchable material is shaped by a mask into a template having a predetermined shape and size, wherein the predetermined shape and size of the template are consistent with the optical material to be processed The shape and size of the components are consistent;

The template and a portion of the semiconductor layer to be processed are removed by an etching process, wherein the semiconductor layer to be processed that remains has a shape and size consistent with the template to form the optical element; and

Positive and negative electrodes are formed that are electrically connected to the epitaxial structure.

In the manufacturing method of the VCSEL device according to the present application, integrally forming a semiconductor layer to be processed on the surface of the epitaxial structure includes: forming the semiconductor layer to be processed on the surface of the epitaxial structure through an epitaxial growth process.

In the preparation method of the VCSEL device according to the present application, the epitaxial growth process is a non-metal vapor deposition process or a metal vapor deposition process.

In the preparation method of the VCSEL device according to the present application, the material for the semiconductor layer to be processed is any one of the following: GaN, Al _X Ga _1-X As (x=0-1), GaAs, lnP, GaN and additives, Al _X Ga _1-X As (x=0-1) and additives, GaAs and additives, lnP and additives.

In the preparation method of a VCSEL device according to the present application, an etchable material is applied on the to-be-processed semiconductor layer, and the etchable material is shaped into a template having a preset shape and size through a mask, including: A layer of photoresist is applied on the to-be-processed semiconductor layer; and the photoresist is exposed to light through the mask having a preset pattern, so as to remove corresponding portions of the photoresist based on the preset pattern part, wherein the optical glue that is retained forms the template having a predetermined shape and size.

In the manufacturing method of the VCSEL device according to the present application, the template has a shape and size consistent with the concave lens to be processed.

In the manufacturing method of the VCSEL device according to the present application, the template has a shape and size consistent with the convex lens to be processed.

In the manufacturing method of the VCSEL device according to the present application, the template has a shape and size consistent with the grating to be processed.

In the manufacturing method of the VCSEL device according to the present application, removing the template and a part of the to-be-processed semiconductor layer by an etching process includes: removing the template and the to-be-processed layer respectively at the same rate by a dry etching process at least a portion of the semiconductor layer.

Further objects and advantages of the present invention will be fully realized by an understanding of the ensuing description and drawings.

These and other objects, features and advantages of the present invention are fully embodied by the following detailed description, drawings and claims.

Description of drawings

These and/or other aspects and advantages of the present application will become more apparent and easier to understand from the following detailed description of embodiments of the present invention in conjunction with the accompanying drawings, wherein:

FIG. 1 illustrates a schematic diagram of a VCSEL device according to an embodiment of the present application.

FIG. 2 illustrates a schematic diagram of a variant implementation of the VCSEL device according to embodiments of the present application.

FIG. 3 illustrates a schematic diagram of another variant implementation of the VCSEL device according to an embodiment of the present application.

FIG. 4 illustrates a flowchart of a method for fabricating the VCSEL device according to an embodiment of the present application.

FIG. 5 illustrates a schematic diagram of a fabrication process of the VCSEL device according to an embodiment of the present application.

FIG. 6 illustrates a schematic diagram of a fabrication process implemented by a variant of the VCSEL device according to an embodiment of the present application.

FIG. 7 illustrates a schematic diagram of a fabrication process performed by another variant of the VCSEL device according to an embodiment of the present application.

Detailed ways

The terms and words used in the following specification and claims are not limited to the bibliographical meanings, but, are merely used by the inventor to enable a clear and consistent understanding of the present application. Accordingly, it is apparent to those skilled in the art that the following description of various embodiments of the present application is provided for illustration purposes only and not for the purpose of limiting the application as defined by the appended claims and their equivalents.

It should be understood that the term "a" should be understood as "at least one" or "one or more", that is, in one embodiment, the number of an element may be one, while in another embodiment, the number of the element may be one. The number may be plural, and the term "one" should not be understood as a limitation on the number.

Although ordinals such as "first," "second," etc. will be used to describe various components, those components are not limited herein. This term is only used to distinguish one component from another. For example, a first component could be termed a second component, and similarly, a second component could be termed a first component, without departing from the teachings of the inventive concept. As used herein, the term "and/or" includes any and all combinations of one or more of the associated listed items.

The terminology used herein is for the purpose of describing the various embodiments only and is not intended to be limiting. As used herein, the singular form is intended to include the plural form as well, unless the context clearly dictates an exception. It will also be understood that the terms "comprising" and/or "having" when used in this specification designate the presence of stated features, numbers, steps, operations, components, elements or combinations thereof, without excluding one or more other features , number, step, operation, component, element, or the presence or addition of a group thereof.

Application overview

As mentioned above, in the existing VCSEL laser package products, the matching accuracy between the VCSEL laser and the optical components is achieved by physical positioning and/or structural cooperation. However, technical solutions relying on physical positioning and/or structural coordination have many defects in practical applications.

First, the positioning accuracy that can be achieved by physical positioning is limited, that is, when the accuracy of the relative positional relationship between the VCSEL laser and the optical components is high, the physical positioning may not meet the application requirements. Secondly, the realization of physical positioning needs to rely on a specific physical structure. Accordingly, the stability of the physical structure will affect the stability of the positioning.

In order to improve the stability between the VCSEL laser and the optical components, some manufacturers choose to directly mount the optical components on the laser exit surface of the VCSEL laser. Although this assembly scheme can improve the coordination stability between the VCSEL laser and optical components to a certain extent, this assembly scheme is still difficult to ensure the positioning and coordination accuracy between the VCSEL laser and the optical components, resulting in the final product formed. It is still difficult to meet the performance requirements.

More specifically, in the process of directly attaching the optical element to the laser emitting surface of the VCSEL laser, since it is difficult to determine the position of the light-emitting hole of the VCSEL laser, it is difficult to precisely align the optical element with the light-emitting hole of the VCSEL laser during the assembly process. Alignment makes it difficult for the laser performance of the final molded VCSEL laser package product to meet the preset requirements.

Moreover, limited by the shape of the optical element itself, it is difficult to mount some optical elements. For example, when the optical element is implemented as a concave lens or a convex lens, the mounting surface of the optical element and the VCSEL laser is not flat. Therefore, , the placement is difficult and it is difficult to ensure placement accuracy.

Also, during the assembly process, adhesives such as glue are used to attach the optical components to the laser exit surface of the VCSEL device. That is, in the packaged product of the VCSEL laser, there may also be an adhesive between the VCSEL laser and the optical element. It should be understood that when the laser light generated by the VCSEL laser passes through the adhesive located between the VCSEL laser and the optical element and reaches the optical element, its optical properties will be affected by the adhesive, resulting in the final projected laser modulated by the optical element. Performance will be affected.

In addition, in the actual industry, the VCSEL laser is usually provided by the chip manufacturer, and the assembly work of the VCSEL packaged product is completed by the packaging factory. That is, from the VCSEL laser to the VCSEL packaged product goes through two nodes in the industry chain. Moreover, in the actual industry, packaging factories may purchase VCSEL lasers provided by different manufacturers. At the same time, problems such as different assembly accuracy may occur during the assembly process, which makes it difficult to ensure the consistency of the final molded VCSEL packaging products.

It is particularly worth mentioning that, since the existing VCSEL laser packaging products are provided by packaging factories, most packaging factories will tend to solve the problems from the perspective of packaging when facing the technical problems of packaging products of VCSEL lasers. This is the technical advantage of the packaging factory, and it is also the unconscious technical blind spot of the packaging factory.

In view of the above technical problems, the inventor of the present application proposes a technical solution for integrating VCSEL lasers and optical elements at the wafer level, starting from the design and manufacturing process of semiconductor products. Specifically, in the design of semiconductor products, relatively precise positioning is achieved between the VCSEL laser and the optical element at the wafer level, so that the VCSEL laser and the optical element in the final molded VCSEL device have relative relative positioning. Higher positioning accuracy.

Also, since the VCSEL laser and the optical element are integrally configured at the wafer level, there are no other redundant components that affect the laser between the VCSEL laser and the optical element, so that the VCSEL device can Laser light modulated by the optical element is projected with relatively high precision.

At the same time, the preparation of the VCSEL device can be completed in a chip manufacturing plant, which improves industrial efficiency. Specifically, during the manufacturing process, the optical element can be precisely formed at the preset position of the VCSEL laser at the wafer level by the existing semiconductor process.

Based on this, the present application proposes a VCSEL device integrated at the wafer level, which includes: an epitaxial structure, which sequentially includes: a substrate, an N-DBR layer, an active region, a confinement layer, and a P-DRB from bottom to top layer, wherein the confinement layer has a confinement hole corresponding to the active region; an optical element integrally formed on the upper surface or the lower surface of the epitaxial structure; and a positive electrode electrically connected to the epitaxial structure and negative electrode.

Based on this, the present application also proposes a method for preparing a VCSEL device, which includes: forming an epitaxial structure through an epitaxial growth process, wherein the epitaxial structure, from bottom to top, includes: a substrate, an N-DBR layer, a a source region, a confinement layer and a P-DRB layer, wherein the confinement layer has confinement holes corresponding to the active region; a semiconductor layer to be processed is integrally formed on the surface of the epitaxial structure; An etchable material is applied to the layer, and the etchable material is shaped by a mask into a template having a predetermined shape and size, wherein the predetermined shape and size of the template are the same as the shape and size of the optical element to be processed. Removing a portion of the template and the semiconductor layer to be processed by an etching process, wherein the semiconductor layer to be processed that is retained has a shape and size consistent with the template to form the optical element; and , forming a positive electrode and a negative electrode electrically connected to the epitaxial structure.

Having introduced the basic principles of the present application, various non-limiting embodiments of the present application will be described in detail below with reference to the accompanying drawings.

Schematic of a VCSEL device integrated at the wafer level

As shown in FIG. 1 , the VCSEL device integrated at the wafer level according to the embodiment of the present application is illustrated, wherein the VCSEL device includes the VCSEL laser 100 and the VCSEL laser 100 integrally formed at the wafer level. The optical element 200 of the laser exit surface, the optical element 200 being configured to modulate the laser light exiting from the laser exit surface.

In the embodiment of the present application, the type of the optical element 200 is not limited by the present application, and includes but is not limited to a convex lens, a concave lens, a grating, and the like. Correspondingly, when the optical element 200 is implemented as a convex lens, the optical element 200 can reduce the beam divergence angle of the laser light emitted from the laser exit surface, as shown in FIG. 1 ; when the optical element 200 is implemented When the optical element 200 is a concave lens, the optical element 200 can increase the divergence angle of the beam emitted from the laser exit surface, as shown in FIG. 2; when the optical element 200 is implemented as a grating, the optical element 200 can control the The wavelength of the laser light emitted from the laser light emitting surface is shown in FIG. 3 .

As shown in FIGS. 1 to 3 , in the embodiment of the present application, the VCSEL laser 100 of the VCSEL device includes: an epitaxial structure 10 and a positive electrode 20 and a negative electrode 30 electrically connected to the epitaxial structure 10 . As shown in FIGS. 1 to 3 , the epitaxial structure 10 of the VCSEL laser 100 includes a substrate 11 , an active region 13 , a first reflector 12 and a second reflector 14 , wherein the active region 13 is set Between the first semiconductor region where the first reflector 12 is formed and the second semiconductor region where the second reflector 14 is formed. The first semiconductor region, the second semiconductor region and the active region 13 are formed on the substrate 11 by an epitaxial growth process (eg, a metal vapor deposition process and/or a non-metal vapor deposition process).

In the embodiment of the present application, the material of the substrate 11 is selected from any one of GaAs, GaN and lnP, which allows the transmission of laser light in the wavelength range of 300 nm to 150 mm. Preferably, the substrate 11 is made of GaAs material, which may be undoped, N-type doped (eg, doped with Si), or P-type doped (eg, doped with Si) doped with Zn). The absorption loss of the substrate 11 made of GaAs material to a specific wavelength of laser light (eg, 980nm band laser) is very small, even negligible (for example, when the substrate 11 is made in an undoped condition, the absorption loss is very small. When completed, its absorption loss can be ignored).

In the embodiments of the present application, the active region 13 includes quantum wells (of course, in other examples of the present application, the active region 13 may include quantum dots), which may be composed of AlInGaAs (for example, AlInGaAs, GaAs, AlGaAs, etc.). and InGaAs), InGaAsP (for example, InGaAsP, GaAs, InGaAs, GaAsP, and GaP), GaAsSb (for example, GaAsSb, GaAs, and GaSb), InGaAsN (for example, InGaAsN, GaAs, InGaAs, GaAsN, and GaN), or AlInGaAsP (for example, AlInGaAsP , AlInGaAs, AlGaAs, InGaAs, InGaAsP, GaAs, InGaAs, GaAsP and GaP). Of course, in the embodiment of the present application, the active region 13 may also be formed by other compositions for forming a quantum well layer.

Said first reflector 12 and said second reflector 14 each comprise a system of alternating layers of materials of different refractive indices forming a Distributed Bragg Reflector. The choice of material for the alternating layers depends on the operating wavelength of the desired laser. For example, in a specific example of the present application, the first reflector 12 and the second reflector 14 may be made of Al _x Ga _1-x As (x=1˜0 ) of alternating layers (in some examples of the present application, the first reflector 12 and the second reflector 14 may even be made without aluminum content, ie, contain no aluminum). It is worth mentioning that the optical thickness of the alternating layers is equal to or approximately equal to 1/4 of the operating wavelength of the laser. Particularly, in the embodiment of the present application, the first reflector 12 is an N-type doped distributed Bragg reflector, that is, an N-DBR layer, and the second reflector 14 is a P-type doped distribution type Bragg reflector, that is, the P-DBR layer.

As shown in FIGS. 1 to 3 , the active region 13 is sandwiched between the first reflector 12 and the second reflector 14 to form a resonant cavity in which photons are excited in The back-and-forth reflection in the resonant cavity is continuously and repeatedly amplified to form laser oscillation, thereby forming laser light. Those of ordinary skill in the art should know that through the configuration and design of the first reflector 12 and the second reflector 14 , the exit direction of the laser light can be selectively controlled, for example, the exit from the second reflector 14 (ie, from the top surface of the VCSEL laser 100 , that is, the laser exit surface of the VCSEL laser 100 is the upper surface of the VCSEL laser 100 ) or from the first reflector 12 (ie, from the VCSEL laser 12 ) The bottom surface of the laser 100 exits, that is, the laser exit surface of the VSCSEL laser is the lower surface of the VCSEL laser 100). In particular, in the embodiment of the present application, the first reflector 12 and the second reflector 14 are designed so that after the laser oscillates in the resonant cavity, it exits from the second reflector 14, and also That is, in the embodiment of the present application, the laser exit surface of the VCSEL laser 100 is the upper surface of the VCSEL laser 100 .

As mentioned above, in this embodiment of the present application, the VCSEL laser 100 further includes a positive electrode 20 and a negative electrode 30 that are electrically connected to the epitaxial structure 10 . Specifically, as shown in FIGS. 1 to 3 , in the embodiment of the present application, the positive electrode 20 is formed on the upper surface of the second reflector 14 , and the negative electrode 30 is formed on the upper surface of the substrate 11 . lower surface. It is worth mentioning that, in other examples of the present application, the positive electrode 20 and the negative electrode 30 may also be disposed at other positions of the epitaxial structure 10 , which is not intended in the present application. For example, in some examples of the present application, the negative electrode 30 may be formed above the second reflector 14, for example, the positive electrode 20 and the negative electrode 30 are arranged on the same plane.

During operation, an operating voltage/current is applied to the positive electrode 20 and the negative electrode 30 of the VCSEL laser 100 to generate current in the semiconductor structure. After being turned on, the flow of current is restricted by the confinement layer 15 formed over the active region 13 , which is finally guided into the middle region of the semiconductor structure, so that laser light is generated in the middle region of the active region 13 . More specifically, as shown in FIGS. 1 to 3 , in the embodiment of the present application, the confinement layer 15 formed above the active region 13 includes a confinement region 151 and a confinement formed by the confinement region 151 Aperture 152, wherein the confinement region 151 has a high resistivity to confine the flow of carriers into the middle region of the semiconductor, and the confinement region 151 has a low refractive index for lateral confinement of photons, carriers and optical Lateral confinement increases the density of carriers and photons in the active region 13 , improving the efficiency of light generation in the active region 13 , and the confinement hole 152 defines the VCSEL laser 100 . Exit aperture.

In some examples of the present application, the confinement layer 15 is implemented as an oxidation confinement layer, which is formed over the active region 13 by an oxidation process. In a specific implementation, the oxidation confinement layer may be formed as a single layer over the active region 13 . Of course, in other specific embodiments, the oxidation confinement layer 15 may also be formed above the active region 13 by oxidizing at least a part of the lower region of the second reflector 14 . For this, and Not limited by this application. In other examples of the present application, the confinement layer 15 may also be implemented in other forms, for example, implemented as an ion confinement layer (not shown in the figure), which is formed on the active region 13 through an ion planting process above, which is not limited by this application.

It should be understood that after the operating voltage/current is applied to the positive electrode 20 and the negative electrode 30 of the VCSEL laser 100, the active region 13 is excited to generate laser light and the laser light is generated between the first reflector 12 and the The second reflectors 14 are reflected and oscillated and then exit from the upper surface of the second reflectors 14 . Correspondingly, as shown in FIG. 1 to FIG. 3 , in the examples of the present application, the optical element 200 integrally formed with the VCSEL laser 100 is located on the exit path of the laser light. Therefore, the optical element 200 can The laser is modulated.

Specifically, in the embodiment of the present application, the optical element 200 is formed on the upper surface of the epitaxial structure 10 by a semiconductor growth process (eg, a non-metal vapor deposition process and/or a metal vapor deposition process). The optical element 200 is made of any one of the following materials: GaN, Al _X Ga _1-X As (x=0˜1), GaAs, lnP, GaN and additives (that is, the optical element 200 is made of In the forming material, the main material is GaN, and the auxiliary material is additive), Al _X Ga _1-X As (x=0-1) and the additive (that is, the main material of the optical element 200 is Al _X Ga _1-X As (x=0-1), the auxiliary material is the additive), GaAs and the additive (that is, the main material of the optical element 200 is GaAs, and the auxiliary material is the additive), lnP and the additive ( That is, the main material of the optical element 200 is lnP, and the auxiliary material is an additive).

It should be noted that, in the embodiment of the present application, the material of the optical element 200 is similar to the material of the substrate 11. Therefore, the preparation and molding process of the optical element 200 can be based on the existing Mature semiconductor process is completed. That is, in the embodiment of the present application, the optical element 200 can be precisely formed at the predetermined position of the VCSEL laser 100 (specifically, the upper surface) and are precisely aligned with the confinement holes 152 of the VCSEL laser 100.

Moreover, it should be noted that in the embodiment of the present application, after the optical element 200 can be precisely formed on the preset position of the VCSEL laser 100 at the wafer level by the existing semiconductor process, the VCSEL laser There are no other redundant parts between 100 and the optical element 200 that will affect the laser, so that the laser light projected by the VCSEL laser 100 can directly reach the optical element 200 and be modulated by the optical element 200 without other extra parts to affect the performance of the laser.

As mentioned above, when the optical element 200 is implemented as a convex lens, the optical element 200 can reduce the beam divergence angle of the laser light emitted from the laser exit surface, as shown in FIG. 1 . When the optical element 200 is implemented as a concave lens, the optical element 200 can increase the divergence angle of the light beam emitted from the laser exit surface, as shown in FIG. 2 . When the optical element 200 is implemented as a grating, the optical element 200 can control the wavelength of the laser light emitted from the laser light exit surface, as shown in FIG. 3 .

In a specific example of the present application, the light source divergence angle of the VCSEL laser 100 is set to be 20°. Under this condition, when the optical element 200 is implemented as a convex lens, and the convex lens is made of a mixed material of lnP and GaAs (the refractive index of the material is n=3.5), and the radius of curvature of the convex lens (1/ With r)=1/71.5 (um ⁻¹ ), the optical element 200 implemented as a convex lens can modulate to emit a collimated light source.

Under this condition, when the optical element 200 is implemented as a convex lens, and the convex lens is made of a mixed material of lnP and GaAs (the refractive index of this material is n=3.5) and the radius of curvature of the convex lens (1/r )>1/71.5(um ^-1 ), the optical element 200 implemented as a convex lens can focus the laser light generated by the VCSEL laser and finally project the focused light, that is, the VCSEL device can be modulated to emit focused light light source.

Under this condition, when the optical element 200 is implemented as a convex lens, and the convex lens is made of GaN material (the refractive index of this material is n=2.33), and the curvature radius of the convex lens (1/r)=1 /38.6 (um ^-1 ), the optical element 200 implemented as a convex lens is capable of modulating a collimated light source.

Under this condition, when the optical element 200 is implemented as a convex lens, and the convex lens is made of GaN material (the refractive index of this material is n=2.33), and the curvature radius of the convex lens (1/r)>1 /38.6 (um ^-1 ), the optical element 200 implemented as a convex lens is capable of focusing the laser light generated by the VCSEL laser and finally projecting a focused light, ie the VCSEL device is capable of modulating a focused light source.

Under this condition, when the optical element 200 is implemented as a convex lens, and the convex lens is made of a mixture of AlGaAs and InGaAs (refractive index of the mixed material n=3.9) and the radius of curvature of the convex lens (1/r ) = 1/83 (um ^-1 ), the optical element 200 implemented as a convex lens can modulate and emit a collimated light source.

Under this condition, when the optical element 200 is implemented as a convex lens, and the convex lens is made of a mixture of AlGaAs and InGaAs (refractive index of the mixed material n=3.9) and the radius of curvature of the convex lens (1/r )>1/83(um ^-1 ), the optical element 200 implemented as a convex lens can focus the laser light generated by the VCSEL laser and finally project the focused light, that is, the VCSEL device can be modulated to emit focused light light source.

In another specific example of the present application, the light source divergence angle of the VCSEL laser 100 is set to be 40°. Under this condition, when the optical element 200 is implemented as a convex lens, and the convex lens is made of a mixed material of lnP and GaAs (the refractive index of the material is n=3.5), and the radius of curvature of the convex lens (1/ With r) = 1/35.8 (um ⁻¹ ), the optical element 200 implemented as a convex lens can modulate to emit a collimated light source.

Under this condition, when the optical element 200 is implemented as a convex lens, and the convex lens is made of a mixed material of lnP and GaAs (the refractive index of this material is n=3.5) and the radius of curvature of the convex lens (1/r )>1/35.8(um ^-1 ), the optical element 200 implemented as a convex lens can focus the laser light generated by the VCSEL laser and finally project the focused light, that is, the VCSEL device can be modulated to emit focused light light source.

Under this condition, when the optical element 200 is implemented as a convex lens, and the convex lens is made of GaN material (the refractive index of this material is n=2.33), and the curvature radius of the convex lens (1/r)=1 /20.3 (um ⁻¹ ), the optical element 200 implemented as a convex lens can modulate a collimated light source.

Under this condition, when the optical element 200 is implemented as a convex lens, and the convex lens is made of GaN material (the refractive index of this material is n=2.33), and the curvature radius of the convex lens (1/r)>1 /20.3 (um ^-1 ), the optical element 200 implemented as a convex lens is capable of focusing the laser light generated by the VCSEL laser and finally projecting a focused light, ie the VCSEL device is capable of modulating a focused light source.

Under this condition, when the optical element 200 is implemented as a convex lens, and the convex lens is made of a mixture of AlGaAs and InGaAs (refractive index of the mixed material n=3.9) and the radius of curvature of the convex lens (1/r ) = 1/38.6 (um ^-1 ), the optical element 200 implemented as a convex lens can modulate and emit a collimated light source.

Under this condition, when the optical element 200 is implemented as a convex lens, and the convex lens is made of a mixture of AlGaAs and InGaAs (refractive index of the mixed material n=3.9) and the radius of curvature of the convex lens (1/r )>1/38.6(um ^-1 ), the optical element 200 implemented as a convex lens can focus the laser light generated by the VCSEL laser and finally project the focused light, that is, the VCSEL device can be modulated to emit focused light light source.

In yet another specific example of the present application, the light source divergence angle of the VCSEL laser 100 is set to be 40°. Under this condition, when the optical element 200 is implemented as a concave lens, and the concave lens is made of a mixed material of lnP and GaAs (the refractive index of the material is n=3.5), and the radius of curvature of the concave lens (1/ When r) = 1/71.5 (um ^-1 ), the optical element 200 implemented as a concave lens can be modulated to make the laser light generated by the VCSEL laser 100 more divergent, specifically, reaching a divergence angle of 60°, also That is, the VCSEL device can modulate and emit a light source with a divergence angle of 60°.

Under this condition, when the optical element 200 is implemented as a concave lens, and the concave lens is made of a mixed material of lnP and GaAs (the refractive index of this material is n=3.5) and the radius of curvature of the concave lens (1/r )>1/71.5(um ^-1 ), the optical element 200 implemented as a concave lens can be modulated to make the laser light generated by the VCSEL laser 100 more divergent, specifically, to reach a divergence angle less than 60°, and also That is, the VCSEL device can modulate and emit light sources with divergence angles less than 60°.

Under this condition, when the optical element 200 is implemented as a concave lens, and the concave lens is made of GaN material (the refractive index of this material is n=2.33), and the curvature radius of the concave lens (1/r)=1 /38.6 (um ⁻¹ ), the optical element 200 implemented as a concave lens can be modulated so that the laser light generated by the VCSEL laser 100 is more divergent, specifically, to a divergence angle of 60°, that is, the The VCSEL device is capable of modulating and emitting a light source with a divergence angle of 60°.

Under this condition, when the optical element 200 is implemented as a concave lens, and the concave lens is made of GaN material (the refractive index of this material is n=2.33), and the curvature radius of the concave lens (1/r)>1 /38.6 (um ⁻¹ ), the optical element 200 implemented as a concave lens can be modulated so that the laser light generated by the VCSEL laser 100 is more divergent, specifically, to a divergence angle less than 60°, that is, the The VCSEL device described is capable of modulating concurrent light sources with divergence angles less than 60°.

Under this condition, when the optical element 200 is implemented as a concave lens, and the concave lens is made of a mixture of AlGaAs and InGaAs (the refractive index of the mixed material is n=3.9) and the radius of curvature of the concave lens (1/r )=1/83(um ⁻¹ ), the optical element 200 implemented as a concave lens can be modulated to make the laser light generated by the VCSEL laser 100 more divergent, specifically, to reach a divergence angle of 60°, that is, , the VCSEL device is capable of modulating and emitting a light source with a divergence angle of 60°.

Under this condition, when the optical element 200 is implemented as a concave lens, and the concave lens is made of a mixture of AlGaAs and InGaAs (the refractive index of the mixed material is n=3.9) and the radius of curvature of the concave lens (1/r )>1/83(um ^-1 ), the optical element 200 implemented as a concave lens can be modulated to make the laser light generated by the VCSEL laser 100 more divergent, specifically, reaching a divergence angle less than 60°, and also That is, the VCSEL device can modulate and emit light sources with divergence angles less than 60°.

It should be understood that, in other examples of the present application, the optical performance of the VCSEL device may be adjusted by adjusting the parameter configuration of the optical element 200 , which is not limited by the present application.

Schematic VCSEL device fabrication method

FIG. 4 illustrates a flowchart of a method for fabricating the VCSEL device according to an embodiment of the present application. As shown in FIG. 4 , the method for fabricating the VCSEL device according to an embodiment of the present application includes: S101 , forming an epitaxial structure through an epitaxial growth process, wherein the epitaxial structure, from bottom to top, sequentially includes: a substrate, A first reflector, an active region, a confinement layer, and a second reflector, wherein the confinement layer has a confinement hole corresponding to the active region; S102, integrally molding a semiconductor to be processed on the surface of the epitaxial structure layer; S103, apply an etchable material on the to-be-processed semiconductor layer, and shape the etchable material into a template with a preset shape and size through a mask, wherein the predetermined shape and size of the template are the same as The shape and size of the optical element to be processed are consistent; S104, the template and a part of the semiconductor layer to be processed are removed through an etching process, wherein the remaining semiconductor layer to be processed has the same shape as the template. shape and size to form the optical element; and, S105 , to form a positive electrode and a negative electrode electrically connected to the epitaxial structure.

In step S101 , an epitaxial structure 10 is formed by an epitaxial growth process, wherein the epitaxial structure 10 includes, from bottom to top, a substrate 11 , a first reflector 12 , an active region 13 , a confinement layer 15 and a second The reflector 14 , wherein the confinement layer 15 has confinement holes 152 corresponding to the active region 13 . That is, through the existing semiconductor growth process, the epitaxial structure 10 of the VCSEL laser is formed, as shown in FIG. 4 .

In step S102, a semiconductor layer 300 to be processed is integrally formed on the surface of the epitaxial structure 10. Specifically, the to-be-processed semiconductor layer 300 is integrally formed on the upper surface or the lower surface of the epitaxial structure 10 through a semiconductor growth process.

In the example shown in FIG. 5 , the to-be-processed semiconductor layer 300 is integrally formed on the upper surface of the epitaxial structure 10 at the wafer level. In this example, the material of the semiconductor layer 300 to be processed is selected from any one of the following materials: GaN, Al _X Ga _1-X As (x=0˜1), GaAs, lnP, GaN and additives, Al _X Ga _1-X As (x=0-1) and additives, GaAs and additives, lnP and additives. It should be noted that the material of the semiconductor layer 300 to be processed is similar to the material of the substrate 11, and accordingly, in this example, a semiconductor growth process (eg, a non-metal vapor deposition process and and/or metal vapor deposition process) to grow the to-be-processed semiconductor layer 300 on the upper surface of the epitaxial structure 10 .

In step S103, an etchable material is applied on the to-be-processed semiconductor layer 300, and the etchable material is shaped into a template 400 with a preset shape and size through a mask, wherein the predetermined size of the template 400 is The shape and size correspond to the shape and size of the optical element 200 to be processed. That is, a template 400 having a predetermined shape and size is formed on the semiconductor layer 300 to be processed, wherein the predetermined shape and size of the template 400 are consistent with the shape and size of the optical element 200 to be processed.

In the example illustrated in FIG. 5 , the optical element 200 to be processed is a convex lens, and the template 400 is consistent with the shape and size of the optical element 200 . And, in this example, the process of applying an etchable material on the to-be-processed semiconductor layer 300 and shaping the etchable material into a template 400 having a preset shape and size through a mask 500 includes: first , a layer of photoresist 600 is applied on the to-be-processed semiconductor layer 300 , that is, in this example, the etchable material is implemented as photoresist 600 .

Then, the photoresist 600 is exposed through the mask 500 having a preset pattern to remove a corresponding portion of the photoresist 600 based on the preset pattern, wherein the remaining photoresist The template 400 is formed having a predetermined shape and size. Specifically, a mask 500 with a preset pattern is suspended above the photoresist 600 , and then the photoresist 600 is exposed through the mask 500 to remove based on the preset pattern Corresponding portions of the photoresist 600, correspondingly, the remaining optical glue forms the template 400 having a predetermined shape and size.

It is worth mentioning that, in other examples of the present application, the etchable material may be implemented as other types of materials, which is not limited by the present application. The preset pattern of the mask 500 is determined based on the optical element 200 to be processed, that is, the pattern of the mask 500 can be adjusted based on the actual situation.

In step S104, the template 400 and a part of the to-be-processed semiconductor layer 300 are removed by an etching process, wherein the remaining to-be-processed semiconductor layer 300 has a shape and size consistent with the template 400, so as to The optical element 200 is formed. Specifically, the template 400 and a part of the to-be-processed semiconductor layer 300 may be removed by a dry etching process or a wet etching process. Accordingly, the remaining to-be-processed semiconductor layer 300 has the same characteristics as the template 400 . Consistent shape and size to form the optical element 200 as shown in FIG. 5 .

Specifically, in the etching process, in order to ensure that the final remaining semiconductor layer 300 to be processed has the same shape and size as the template 400 , the etching speed and the etching area should be precisely controlled. In a specific example, the template 400 and at least a part of the semiconductor layer 300 to be processed are respectively removed at the same rate through a dry etching process, so that the semiconductor layer 300 to be processed that remains finally has the same characteristics as the semiconductor layer 300 to be processed. The template 400 is consistent in shape and size to form the optical element 200 .

In step S105, a positive electrode 20 and a negative electrode 30 electrically connected to the epitaxial structure 10 are formed. That is, the positive electrode 20 and the negative electrode 30 for turning on the VCSEL laser are formed. Particularly, in the example shown in FIG. 5 , the positive electrode 20 is formed on the upper surface of the epitaxial structure 10 through a growth process, and the negative electrode 30 is formed on the lower surface of the epitaxial structure 10 through a growth process (ie, the lower surface of the substrate 11).

It is worth mentioning that although the positive electrode 20 and the negative electrode 30 are formed after the optical element 200 as an example, it should be understood that in other examples of the present application, the positive electrode 20 may also be formed first and the negative electrode 30, and then the optical element 200 is formed through the above process, which is not limited by the present application.

To sum up, the fabrication method of the VCSEL device based on the embodiments of the present application has been clarified that the existing semiconductor process precisely shapes the optical element 200 at the predetermined position of the VCSEL laser 100 at the wafer level.

6 and 7 illustrate two variant implementations of the VCSEL device according to embodiments of the present application. As shown in Figures 6 and 7, in this variant embodiment, the optical element 200 is implemented as a concave lens and a grating, respectively. That is, in step S103, the template 400 is implemented to have the shape and size of a concave lens, and to have the shape and size of a grating, respectively.

It should be understood that, in this embodiment of the present application, when the optical element 200 is implemented as other types of optical elements 200 , it is only necessary to change the size of the template 400 (that is, to change the predetermined pattern of the mask 500 ). Preset shapes and sizes are sufficient. That is, according to the preparation method of the VCSEL device provided in the present application, it has a wide application area.

The basic principles of the present application have been described above in conjunction with specific embodiments. However, it should be pointed out that the advantages, advantages, effects, etc. mentioned in the present application are only examples rather than limitations, and these advantages, advantages, effects, etc., are not considered to be Required for each embodiment of this application. In addition, the specific details disclosed above are only for the purpose of example and easy understanding, rather than limiting, and the above-mentioned details do not limit the application to be implemented by using the above-mentioned specific details.

The block diagrams of devices, apparatus, apparatuses, and systems referred to in this application are merely illustrative examples and are not intended to require or imply that the connections, arrangements, or configurations must be in the manner shown in the block diagrams. As those skilled in the art will appreciate, these means, apparatuses, apparatuses, systems may be connected, arranged, configured in any manner. Words such as "including", "including", "having" and the like are open-ended words meaning "including but not limited to" and are used interchangeably therewith. As used herein, the words "or" and "and" refer to and are used interchangeably with the word "and/or" unless the context clearly dictates otherwise. As used herein, the word "such as" refers to and is used interchangeably with the phrase "such as but not limited to".

It should also be pointed out that in the apparatus, equipment and method of the present application, each component or each step can be decomposed and/or recombined. These disaggregations and/or recombinations should be considered as equivalents of the present application.

The above description of the disclosed aspects is provided to enable any person skilled in the art to make or use this application. Various modifications to these aspects will be readily apparent to those skilled in the art, and the generic principles defined herein may be applied to other aspects without departing from the scope of the application. Therefore, this application is not intended to be limited to the aspects shown herein but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.

The foregoing description has been presented for the purposes of illustration and description. Furthermore, this description is not intended to limit the embodiments of the application to the forms disclosed herein. Although a number of example aspects and embodiments have been discussed above, those skilled in the art will recognize certain variations, modifications, changes, additions and sub-combinations thereof.

Claims (16)

1. A VCSEL device integrated at a wafer level, comprising:

epitaxial structure, it includes in proper order from bottom to top: the semiconductor device comprises a substrate, a first reflector, an active region, a limiting layer and a second reflector, wherein the limiting layer is provided with a limiting hole corresponding to the active region;

an optical element integrally formed on the upper surface or the lower surface of the epitaxial structure; and

a positive electrode and a negative electrode electrically connected to the epitaxial structure.

2. A VCSEL device integrated at a wafer level in accordance with claim 1, wherein the optical element is grown on an upper surface of the epitaxial structure by a semiconductor growth process.

3. A VCSEL device integrated at the wafer level as in claim 2, wherein the optical element is made of a material selected from any of the following: gaN, al _X Ga _1-X As (x =0 to 1), gaAs, lnP, gaN, an additive, and Al _X Ga _1-X As (x =0 to 1) and additives, gaAs and additives, lnP and additives.

4. A VCSEL device integrated at the wafer level in accordance with claim 2, wherein the optical element is a concave or convex lens.

5. A VCSEL device integrated at the wafer level as in claim 2, wherein the optical element is a grating.

6. A wafer level integrated VCSEL device in accordance with claim 1, wherein said confinement layer is an oxidized confinement layer.

7. A wafer level integrated VCSEL device in accordance with claim 1, wherein said confinement layer is an ion confinement layer.

8. A method of fabricating a VCSEL device, comprising:

forming an epitaxial structure through an epitaxial growth process, wherein the epitaxial structure sequentially comprises from bottom to top: the semiconductor device comprises a substrate, a first reflector, an active region, a limiting layer and a second reflector, wherein the limiting layer is provided with a limiting hole corresponding to the active region;

integrally forming a semiconductor layer to be processed on the surface of the epitaxial structure;

applying an etchable material on the semiconductor layer to be processed and shaping the etchable material through a mask into a template having a predetermined shape and size, wherein the predetermined shape and size of the template corresponds to the shape and size of the optical element to be processed;

removing the template and a portion of the semiconductor layer to be processed by an etching process, wherein the remaining semiconductor layer to be processed has a shape and a size conforming to the template to form the optical element; and

forming a positive electrode and a negative electrode electrically connected to the epitaxial structure.

9. A method for fabricating a VCSEL device in accordance with claim 8, wherein integrally forming a semiconductor layer to be processed on a surface of the epitaxial structure comprises:

and forming the semiconductor layer to be processed on the surface of the epitaxial structure by an epitaxial growth process.

10. The method of fabricating a VCSEL device of claim 9, wherein the epitaxial growth process is a non-metal vapor deposition process and/or a metal vapor deposition process.

11. A method for fabricating a VCSEL device in accordance with claim 9, wherein a material of the semiconductor layer to be processed is selected from any one of: gaN, al _X Ga _1-X As (x =0 to 1), gaAs, lnP, gaN, an additive, and Al _X Ga _1-X As (x =0 to 1) and additives, gaAs and additives, lnP and additives.

12. The method of claim 8, wherein applying an etchable material on the semiconductor layer to be processed and shaping the etchable material through a mask into a template having a predetermined shape and size comprises:

applying a layer of photoresist on the semiconductor layer to be processed;

exposing the photoresist through the mask having a preset pattern to remove a corresponding portion of the photoresist based on the preset pattern, wherein the remaining photoresist forms the template having a preset shape and size.

13. A method of fabricating a VCSEL device in accordance with claim 12, wherein the template has a shape and dimensions that conform to a concave lens to be processed.

14. A method of fabricating a VCSEL device in accordance with claim 12, wherein the template has a shape and dimensions that conform to the convex lens to be processed.

15. A VCSEL device integrated at the wafer level as in claim 12, wherein the template has a shape and dimensions consistent with the grating to be processed.

16. A method of fabricating a VCSEL device in accordance with claim 8, wherein removing the template and a portion of the semiconductor layer to be processed by an etching process comprises:

and respectively removing the template and at least one part of the semiconductor layer to be processed at the same rate through a dry etching process.

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