Laser chip, laser transmitter, laser radar and electronic equipment

Abstract

The embodiment of the invention discloses a laser chip, a laser transmitter, a laser radar and electronic equipment, relates to the technical field of semiconductor lasers, and aims to reduce the size of an existing laser transmitter and reduce the cost. The laser chip comprises a laser module and a plurality of micro-nano structure units. The laser module comprises a plurality of light emitting units used for emitting laser beams. The light-emitting units are distributed in an array. A plurality of light outlets are formed in the laser module, and the light outlets are distributed at intervals in an array mode. The plurality of light outlets can respectively correspond to the plurality of light emitting units. And laser beams emitted by the plurality of light emitting units are respectively emitted through the plurality of light outlets. The multiple micro-nano structure units are arranged at the multiple light outlets respectively, and any light outlet is provided with one micro-nano structure unit. The micro-nano structure unit comprises a plurality of micro-nano structures which are distributed at intervals. In the micro-nano structure units at the plurality of light outlets, at least one of the distribution, the number and the size of the plurality of micro-nano structures in at least part of the micro-nano structure units is different.

Description

Technical Field

[0001] The present application relates to the field of semiconductor laser technology, and in particular to a laser chip, a laser transmitter, a laser radar and an electronic device. Background Art

[0002] LiDAR (light detection and ranging) is a radar device that uses lasers for distance detection and 3D modeling. LiDAR has extremely wide applications in many fields such as consumer electronics, autonomous driving, augmented reality (AR), virtual reality (VR), robots and drones.

[0003] LiDAR can be divided into scanning LiDAR and global Flash LiDAR. Scanning LiDAR has a higher cost due to the need to set up a scanning device. Global Flash LiDAR includes a transmitter and a receiver, and the transmitter is used to emit a laser signal with a light field pattern with a certain viewing angle range. The laser signal is reflected by the detected object and received by the receiver, and after signal processing and calculation, 3D information within the entire viewing angle range is obtained. Among them, the existing transmitter includes a packaging tube shell, a laser chip, a shaping lens group and a beam shaper (diffractive optical element, DOE). The laser chip, the shaping lens group and the beam shaper are all arranged in the packaging tube shell. In addition, the shaping lens group and the beam shaper are sequentially located on the light output side of the laser chip.

[0004] Since the package shell needs to reserve installation space for the shaping lens group and the beam shaper, the size and thickness of the packaged transmitting end are relatively large. In addition, the shaping lens group and the beam shaper require a relatively complex assembly process, resulting in a relatively high overall cost of the entire device. Summary of the invention

[0005] The embodiments of the present application provide a laser chip, a laser transmitter, a laser radar and an electronic device, which reduce the volume of the existing laser transmitter and reduce the cost.

[0006] In order to achieve the above objectives, this application adopts the following technical solutions:

[0007] In a first aspect, an embodiment of the present application provides a laser chip. The laser chip includes a laser module and a plurality of micro-nano structure units. Among them, the laser module includes a plurality of light-emitting units, which are used to emit laser beams. The plurality of light-emitting units are distributed in an array. The laser module is formed with a plurality of light outlets, and the plurality of light outlets are spaced apart and distributed in an array. Moreover, the plurality of light outlets may correspond to the plurality of light-emitting units, respectively. The laser beams emitted by the plurality of light-emitting units are emitted through the plurality of light outlets, respectively. The plurality of micro-nano structure units are respectively arranged at the plurality of light outlets, and a micro-nano structure unit is provided at any light outlet. The micro-nano structure unit includes a plurality of micro-nano structures, and the plurality of micro-nano structures are spaced apart. Moreover, in the micro-nano structure units at the plurality of light outlets, at least one of the distribution, quantity and size of the plurality of micro-nano structures in at least some of the micro-nano structure units is different.

[0008] Compared with the prior art, in the laser chip of the embodiment of the present application, each micro-nano structure is equivalent to a free-form surface lens, and the multiple micro-nano structures in each micro-nano structure unit can respectively shape and collimate the laser beam emitted from the light outlet of the corresponding light-emitting unit. The multiple micro-nano structures in the multiple micro-nano structure units can respectively shape and collimate the laser beams emitted by the multiple light-emitting units. In addition, since at least one of the distribution, quantity and size of the multiple micro-nano structures in at least a part of the micro-nano structure units is different, the light beams emitted by at least a part of the multiple light-emitting units can be shaped differently, so that various final required light field patterns can be obtained. When the laser chip of the embodiment of the present application is applied to a laser transmitter, the laser chip itself has the functions of shaping and collimation, and does not require a shaping module and a beam shaper, which greatly reduces the volume and weight of the laser transmitter, and at the same time reduces the cost of the laser transmitter. In addition, the energy value of the multiple laser beams shaped by the multiple micro-nano structure units is high, and the detection distance is far, which is suitable for long-distance measurement.

[0009] In addition, according to the application scenarios and requirements of the laser chip, the distribution density, quantity and size of the multiple micro-nano structures in the multiple micro-nano structure units can be designed to be different, so that the laser beam emitted by the laser chip has different divergence angles. For example, designing the laser chip to have a larger divergence angle can make the applied laser radar have a larger 3D (dimensions) detection angle. Therefore, the laser chip of the embodiment of the present application has a higher degree of design freedom and can be applied to different application scenarios and requirements.

[0010] Furthermore, the micro-nano structures in the micro-nano structure unit can adopt different shapes. In some embodiments of the present application, the micro-nano structure is in a cylindrical shape. The cylindrical micro-nano structure has a higher wave number shaping efficiency.

[0011] For the columnar micro-nano structure, in some embodiments of the present application, the distance between two adjacent micro-nano structures in the micro-nano structure unit is less than half of the working wavelength of the laser beam emitted by the corresponding light-emitting unit. Thus, the wavelength of the micro-nano structure is less than half of the working wavelength of the laser beam emitted by the corresponding light-emitting unit, which can suppress high-order diffraction and improve the shaping quality of the laser beam.

[0012] In some other embodiments of the present application, the micro-nano structure is in the shape of a ring. In addition, the multiple micro-nano structures in the micro-nano structure unit can be nested from the inside to the outside. The manufacturing process of the ring-shaped micro-nano structure is relatively easy and convenient to process.

[0013] For the annular micro-nano structure, in some embodiments of the present application, the radial period of the micro-nano structure in the micro-nano structure unit is less than half of the working wavelength of the laser beam emitted by the corresponding light-emitting unit, thereby suppressing high-order diffraction and improving the shaping quality of the laser beam.

[0014] Furthermore, to meet different semiconductor process manufacturing requirements, in some embodiments of the present application, the average extinction coefficient k of the material of the micro-nano structure in the working band is less than or equal to 0.1. For example, the micro-nano structure is made of gallium arsenide or polycrystalline silicon. For another example, the micro-nano structure can be a micro-nano hole.

[0015] Based on the structure of the laser chip, the light emitting unit may be a vertical cavity surface emitting laser (VCSEL) light emitting unit. Furthermore, the laser chip may be a front-emitting vertical cavity surface emitting laser or a back-emitting vertical cavity surface emitting laser.

[0016] Therefore, in some embodiments of the present application, the laser module further comprises a substrate, and the substrate has a first surface and a second surface arranged opposite to each other. A plurality of light outlets are respectively located on the first surface of the substrate, and a plurality of light emitting units are all located on the second surface of the substrate. Therefore, the laser chip is a back-emitting vertical cavity surface emitting laser. Since the substrate layer can be directly used as a spacer layer between the micro-nano structure unit and the light emitting unit, the shaping effect of the laser beam is better, and there is no need to increase the thickness of the spacer layer.

[0017] In some other embodiments of the present application, the laser module further comprises a substrate, and the substrate has a first surface and a second surface arranged opposite to each other. The plurality of light emitting units are all located on the same surface of the substrate, such as the first surface. The plurality of light outlets are respectively arranged on the surface of one side of the plurality of light emitting units away from the substrate. Therefore, the laser chip is a front-emitting vertical cavity surface emitting laser, and when manufacturing a plurality of micro-nano structure units, there is no loss to the substrate.

[0018] In the second aspect, the embodiment of the present application also includes a laser transmitter, including a packaging structure and the laser chip described in the above embodiment. A mounting cavity is formed in the packaging structure, and the laser chip can be packaged in the mounting cavity. Since the laser chip in the laser transmitter of the embodiment of the present application has the same structure as the laser chip described in the above embodiment, the two can solve the same technical problems and obtain the same technical effects, and will not be described in detail here.

[0019] In a third aspect, an embodiment of the present application provides a laser radar, comprising a circuit board and the laser emitter described in the above embodiment, wherein the laser emitter is electrically connected to the circuit board. Since the laser emitter in the laser radar of the embodiment of the present application has the same structure as the laser emitter described in the above embodiment, both can solve the same technical problems and obtain the same technical effects, and will not be described in detail here.

[0020] Furthermore, in some embodiments of the present application, the above-mentioned circuit board is provided with a laser driving circuit, and the laser driving circuit is connected to multiple light-emitting units of the laser chip in the laser transmitter. The laser driving circuit is used to control the multiple light-emitting units to emit light or turn off. Therefore, the laser chip can be lit up in different areas. Multiple light-emitting units can be quickly lit up in different areas in sequence, which reduces the power consumption of the laser chip and is conducive to the application in consumer electronic products such as mobile phones and tablets.

[0021] In a fourth aspect, an embodiment of the present application provides an electronic device, including a controller and the laser radar described in the above embodiment, wherein the laser radar is electrically connected to the controller. Since the laser radar in the electronic device of the embodiment of the present application has the same structure as the laser transmitter described in the above embodiment, both can solve the same technical problems and obtain the same technical effects, and will not be described in detail here. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] In order to illustrate the technical solution of the embodiments of the present application, the drawings required for use in the embodiments of the present application will be described below.

[0023] Figure 1 This is a schematic diagram of the structure of the laser radar in the embodiment of the present application;

[0024] Figure 2 This is a schematic diagram of the structure of a laser transmitter in a laser radar according to an embodiment of the present application;

[0025] Figure 3 It is a structural schematic diagram of a laser transmitter in the related art;

[0026] Figure 4 This is a schematic diagram of the three-dimensional structure of a laser chip in a laser transmitter according to an embodiment of the present application;

[0027] Figure 5This is a partial cross-sectional schematic diagram of a laser chip according to an embodiment of the present application;

[0028] Figure 6 for Figure 4 A magnified view of part A in FIG.

[0029] Figure 7 A top view of the laser chip according to an embodiment of the present application;

[0030] Figure 8 for Figure 7 A magnified view of part B in FIG.

[0031] Fig. 9 for Figure 8 The enlarged view of the C part in FIG.

[0032] Fig.10 This is a schematic structural diagram of a laser chip having a cylindrical micro-nano structure according to an embodiment of the present application;

[0033] Fig.11 This is a schematic structural diagram of a laser chip having a ring-shaped micro-nano structure according to an embodiment of the present application;

[0034] Fig.12 This is a schematic diagram of the structure of the micro-nano hole in the laser chip of the embodiment of the present application;

[0035] Fig.13 This is a cross-sectional schematic diagram of a laser chip in an embodiment of the present application that is a back-emitting vertical cavity surface emitting laser;

[0036] Fig.14 This is a cross-sectional schematic diagram of a laser chip in an embodiment of the present application that is a front-emitting vertical cavity surface emitting laser;

[0037] Fig.15 is a partial cross-sectional schematic diagram of the laser chip of Example 1;

[0038] Fig.16 (a) and (b) are partial process flow charts for manufacturing the first laser chip in Example 1;

[0039] Fig.17 (a), (b), and (c) are partial process flow charts for manufacturing the second laser chip in Example 1;

[0040] Fig.18 is a partial cross-sectional schematic diagram of the laser chip of Example 2;

[0041] Fig.19 (a), (b), (c), and (d) are partial process flow charts for manufacturing the first laser chip in Example 2;

[0042] Fig. 20(a), (b), (c), (d), and (e) are partial process flow charts for manufacturing the second laser chip in Example 2;

[0043] Fig.21 is a partial cross-sectional schematic diagram of the laser chip of Example 3;

[0044] Fig. 22 (a) and (b) are partial process flow charts for manufacturing the first laser chip in Example 3;

[0045] Fig.23 (a), (b), and (c) are partial process flow charts for manufacturing the first laser chip in Example 3.

[0046] Figure Number:

[0047] 1000-laser radar; 100-housing; 101-accommodating cavity; 200-laser transmitter; 1-laser chip; 11-laser module; 110-light outlet; 111-light-emitting unit; 1111-N-type Bragg reflector; 1112-active layer; 1113-P-type Bragg reflector; 112-substrate; 112a-first surface; 112b-second surface; 12-micro-nano structure unit; 121-micro-nano structure; 121a-micro-nano hole; 1210-micro-nano structure layer; 13-insulating layer; 14-N-type electrode layer; 15-P-type electrode layer; 16-oxide layer; 161-oxide hole; 2-packaging structure; 03-shaping lens group; 04-beam shaper; 300-laser receiver; 400-circuit board. DETAILED DESCRIPTION

[0048] In order to make the objectives, technical solutions and advantages of the present application clearer, the present application will be further described in detail below in conjunction with the accompanying drawings.

[0049] 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 features. In the description of this application, unless otherwise specified, "plurality" means two or more.

[0050] In addition, in the present application, directional terms such as "up", "down", "left", "right", "horizontal" and "vertical" 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 may change accordingly according to the changes in the orientation of the components in the drawings.

[0051] In this application, unless otherwise clearly specified and limited, the term "connection" should be understood in a broad sense. For example, "connection" can refer to the connection of mechanical structure or physical structure. For example, it can be a fixed connection, a detachable connection, or an integrated connection; it can be directly connected or indirectly connected through an intermediate medium. It can also be understood as the physical contact and electrical conduction of components, and it can also be understood as the form in which different components in the circuit structure are connected through physical lines such as PCB copper foil or wires that can transmit electrical signals.

[0052] An embodiment of the present application provides a laser radar, which is a radar system that emits laser beams to detect characteristic quantities such as the position and speed of a target. Figure 1 A specific embodiment of the laser radar of the present application is shown.

[0053] Reference Figure 1 , the laser radar 1000 includes a housing 100, a laser transmitter 200, a laser receiver 300 and a circuit board 400. Among them, a housing 100 is provided with a housing 101. The laser transmitter 200 is a laser transmitting device in the laser radar 1000, which is used to transmit laser light toward a target object. The laser receiver 300 is a laser receiving device in the laser radar 1000, and is used to receive laser light reflected by a target object. The laser transmitter 200 and the laser receiver 300 are both arranged (such as welded) on the circuit board 400 to form a circuit board assembly. The circuit board assembly is arranged in the housing 101 of the housing 100. The circuit board 400 is provided with a signal processing circuit, and the signal processing circuit is electrically connected to the transmitter 200 and the receiver 300 respectively. The signal processing circuit is used to control the laser emission of the laser transmitter 200, process the laser signal received by the laser receiver 300, and calculate information such as the position, speed, distance and size of the target object.

[0054] Among them, Figure 2 As shown, the laser transmitter 200 includes a laser chip 1 and a packaging structure 2. The laser chip 1 can be packaged in the packaging structure 2. The packaging structure 2 can be Figure 2 In some laser transmitters 200, as shown in the package tube shell. Figure 3 As shown, the laser transmitter 200 further includes a shaping lens group 03 and a beam shaper 04, which shapes the laser beam emitted by the laser chip 1 to obtain a desired light spot. However, the packaging tube shell of this laser transmitter 200 has a large volume and thickness, and requires a complex assembly process to assemble the shaping lens group 03 and the beam shaper 04, resulting in a relatively high overall cost of the entire laser transmitter 200.

[0055] At present, in many application scenarios, miniaturization requirements are put forward for the laser radar 1000. Therefore, it is necessary to reduce the volume of the laser emitter 200 in the laser radar 1000. The present application provides an improved laser chip 1, which does not require the shaping lens group 03 and the beam shaper 04 to be set in the packaging structure 2, thereby reducing the volume of the laser emitter 200 and reducing the cost.

[0056] Reference Figure 4 and Figure 5 The laser chip 1 of the embodiment of the present application includes a laser module 11 and a plurality of micro-nano structure units 12. The laser module 11 includes a plurality of light-emitting units 111, and the plurality of light-emitting units 111 may be distributed in an array. For example, Figure 4 The multiple light-emitting units shown are distributed in a rectangular array. Any light-emitting unit 111 is used to emit a laser beam. In addition, the laser module 11 is formed with a plurality of light outlets 110, and the plurality of light outlets 110 are spaced apart and distributed in an array. In addition, the plurality of light outlets 110 may correspond to the plurality of light-emitting units 111, respectively. The laser beams emitted by the plurality of light-emitting units 111 are emitted through the corresponding light outlets 110, respectively. The above-mentioned plurality of micro-nano structure units 12 are respectively arranged at the plurality of light outlets 110. In addition, a micro-nano structure unit 12 is provided at any light outlet 110. Each micro-nano structure unit 12 includes the following: Figure 6 The plurality of micro-nano structures 121 shown are spaced apart. For example, the plurality of micro-nano structures 121 are spaced apart. Figure 7 and Figure 8 The circular array distribution shown. For another example, the multiple micro-nano structures 121 are distributed in a rectangular array. Moreover, among the multiple micro-nano structure units 12 at the multiple light outlets 110, at least one of the distribution, quantity and size of the multiple micro-nano structures 121 in at least some of the micro-nano structure units 12 is different. That is, in a part of the multiple micro-nano structure units 12, any one, any two or three of the distribution, quantity and size of the multiple micro-nano structures 121 in the micro-nano structure unit 12 are different. Alternatively, in the multiple micro-nano structure units 12, any one, any two or three of the distribution, quantity and size of the multiple micro-nano structures 121 in the micro-nano structure unit 12 are different.

[0057] Each of the above-mentioned micro-nano structures 121 is equivalent to a free-form surface lens, and the multiple micro-nano structures 121 in each micro-nano structure unit 12 can respectively shape, collimate, etc. the laser beam emitted from the corresponding light-emitting unit 111 from the light outlet 110. The multiple micro-nano structures 121 in the multiple micro-nano structure units 12 can respectively shape, collimate, etc. the laser beams emitted from the multiple light-emitting units 111.

[0058] Figure 7A schematic diagram showing a plurality of micro-nano structure units 12 arrayed and distributed in a laser module 11 is shown. Figure 8 Shows Figure 7 An enlarged view of a micro-nano structure unit 12. Fig. 9 FIG. 1 shows a partial enlarged view of a micro-nano structure unit 12. Fig. 9 It can be seen that the distribution density and size of the multiple micro-nano structures 121 in the micro-nano structure unit 12 are different.

[0059] Due to the different distribution, number or size of the multiple micro-nano structures 121 in the micro-nano structure unit 12, the shaping effect of the emitted laser beam is different, such as the divergence angle of the laser beam. Therefore, in the embodiment of the present application, at least some of the micro-nano structure units 12 have different shaping effects on the emitted laser beam, and the laser beams emitted by the multiple array-distributed light-emitting units 111 can be shaped differently, so that various final required light field patterns can be obtained. When the laser chip 1 of the embodiment of the present application is applied to the laser emitter 200, the laser chip 1 itself has the functions of shaping and collimation, and does not require a shaping module and a beam shaper 04, which greatly reduces the volume and weight of the laser emitter 200, and at the same time reduces the cost of the laser emitter 200. Compared with the use of a light homogenizer to shape the emitted light beam of the laser chip 1, the energy value of the multiple laser beams shaped by the laser chip 1 of the embodiment of the present application after multiple micro-nano structure units 12 is higher, and the detection distance is longer, which can be used for long-distance measurement.

[0060] It should be noted that the electrical control system of the laser chip 1 can be arranged on the circuit board 400 of the laser radar 1000. In some embodiments, the circuit board 400 in the laser radar 1000 is also provided with a laser driving circuit, and the laser driving circuit can be connected to the multiple light-emitting units 111 in the laser chip 1. In addition, the laser driving circuit can also be electrically connected to the signal processing circuit. The laser driving circuit is used to control the multiple light-emitting units 111 in the laser chip 1 to light up or turn off respectively. Therefore, the signal processing circuit can realize the partition lighting of the laser chip 1 through the laser driving circuit. For example, multiple light-emitting units 111 can be quickly and sequentially partitioned, which reduces the power consumption of the laser chip 1, which is conducive to application in consumer electronic products such as mobile phones and tablets.

[0061] The internal structure of the above-mentioned laser chip 1 is further described. It can be understood that, according to the application scenarios and requirements of the laser radar 1000, the laser chip 1 can have different divergence angles by designing the distribution density, quantity and size of the micro-nano structures 121 in the multiple micro-nano structure units 12, or any combination of the sizes of the multiple micro-nano structures 121. The laser chip 1 of the embodiment of the present application has a higher degree of design freedom and can be applied to different application scenarios and requirements. Among them, if the laser chip 1 has a larger emission angle, the laser radar 1000 can have a larger 3D detection viewing angle. Thus, the laser chip 1 is suitable for some application scenarios that have higher requirements on the detection viewing angle.

[0062] Furthermore, in the laser chip 1 of the embodiment of the present application, the micro-nano structure 121 can be made into various shapes, which is not limited in the present application. Fig.10 As shown, the shape of the micro-nano structure 121 is a column, specifically a cylindrical shape. The columnar micro-nano structure 121 has a higher beam shaping efficiency.

[0063] For the columnar micro-nano structure 121, the desired shaping effect can be obtained by designing the spacing L between two adjacent micro-nano structures 121. In some embodiments of the present application, the spacing L between two adjacent micro-nano structures 121 in the micro-nano structure unit 12 is less than half of the working wavelength of the laser beam emitted by the corresponding light-emitting unit 111. Thus, the wavelength of the micro-nano structure 121 is less than half of the working wavelength of the laser beam emitted by the corresponding light-emitting unit 111, which can suppress high-order diffraction and improve the shaping quality of the laser beam.

[0064] For example, in some embodiments of the present application, Fig.11 As shown, the micro-nano structure 121 is in the shape of a ring. In addition, in a micro-nano structure unit 12, a plurality of micro-nano structures 121 are nested from the inside to the outside. The processing difficulty of the ring-shaped micro-nano structure 121 is relatively lower, and it is easy to process and manufacture.

[0065] For the annular micro-nano structure 121, the desired shaping effect can be obtained by setting the radial period of the micro-nano structure 121. In some embodiments of the present application, the radial period of the micro-nano structure 121 in the micro-nano structure unit 12 is less than half of the working wavelength of the laser beam emitted by the corresponding light emitting unit 111. Thus, high-order diffraction can be suppressed and the shaping quality can be improved.

[0066] It should be noted that the micro-nano structure 121 may have a physical structure or may not have a physical structure. Not having a physical structure means that the micro-nano structure 121 is Fig.12 The micro-nano hole 121a is shown. The present application does not limit the specific structural form of the micro-nano structure 121.

[0067] According to the semiconductor process manufacturing requirements and optical properties of the laser chip 1, the micro-nano structure 121 needs to use suitable materials. In some embodiments of the present application, the above-mentioned micro-nano structure 121 uses a material with an average extinction coefficient k≤0.1 in the working band. For example, the micro-nano structure 121 with a solid structure, the material of the micro-nano structure 121 is gallium arsenide or polycrystalline silicon. For another example, for the micro-nano hole 121a, the material of the micro-nano hole 121a can be regarded as air, and the material forming the hole wall of the micro-nano hole 121a can be silicon dioxide. Therefore, on the basis of meeting the optical shaping, it can be applicable to various semiconductor process manufacturing requirements.

[0068] The above is mainly an explanation of the shape, material and parameter design of the micro-nano structure 121. The laser chip 1 of the embodiment of the present application is a vertical cavity surface emitting laser, which can be a front-emitting vertical cavity surface emitting laser or a back-emitting vertical cavity surface emitting laser, and the present application does not limit this. Therefore, the light-emitting unit 111 of the embodiment of the present application is a light-emitting unit 111 of a vertical cavity surface emitting laser.

[0069] In addition, the laser module 11 further includes: Fig.13 The substrate 112 shown has a first surface 112a and a second surface 112b that are arranged opposite to each other. The plurality of light-emitting units 111 can be arranged on the first surface 112a or on the second surface 112b, and the present application does not limit this. Depending on the location of the light-emitting unit 111, the location of the micro-nano structure 121 relative to the substrate 112 is different.

[0070] In some embodiments of the present application, Fig.13 As shown, a plurality of light-emitting units 111 are located on the second surface 112b, and a plurality of light outlets 110 are respectively located on the first surface 112a of the substrate 112. A plurality of micro-nano structure units 12 are respectively located at the plurality of light outlets 110. That is, the laser chip 1 is a back-emitting vertical cavity surface emitting laser. Since the substrate 112 of the vertical cavity surface emitting laser can be directly used as a spacer layer between the micro-nano structure unit 12 and the light-emitting unit 111, the shaping effect of the laser beam is better, and there is no need to increase the thickness of the spacer layer.

[0071] In other embodiments of the present application, Fig.14 As shown, the above-mentioned multiple light-emitting units 111 are located on the second surface 112b of the substrate 112. Multiple light outlets 110 are respectively arranged on the surface of one side of the multiple light-emitting units 111 away from the substrate 112. Multiple micro-nano structure units 12 are respectively located at the multiple light outlets 110. That is, the laser chip 1 is a front-emitting vertical cavity surface emitting laser. At this time, when the multiple micro-nano structure units 12 are manufactured, there is no loss to the substrate 112.

[0072] The specific hierarchical structure of the laser chip 1 of the present application is further described below in conjunction with several specific embodiments of the laser chip 1 .

[0073] Example 1

[0074] The laser chip 1 in this example is a back-emitting vertical cavity surface emitting laser. Fig.15 The laser chip 1 includes a substrate 112, a plurality of light emitting units 111, an insulating layer 13, an N-type electrode layer 14, a P-type electrode layer 15, an oxide layer 16 and a plurality of micro-nano structure units 12. The substrate 112 has a first surface 112a and a second surface 112b. The first surface 112a is Fig.15 The upper surface of the substrate 112 shown in FIG. 1 is a second surface 112b. Fig.15 The lower surface of the substrate 112 is shown. The light outlets 110 of the plurality of light emitting units 111 are respectively located on the first surface 112a of the substrate 112. The plurality of micro-nano structure units 12 are all located on the first surface 112a of the substrate 112. The plurality of light emitting units 111 are respectively arranged on the second surface 112b of the substrate 112.

[0075] Any light-emitting unit 111 includes an N-type Bragg reflector 1111, an active layer 1112 and a P-type Bragg reflector 1113, wherein the N-type Bragg reflector 1111, the active layer 1112, the insulating layer 13, the oxide layer 16 and the P-type Bragg reflector 1113 are sequentially stacked on the second surface 112b of the substrate 112. Among them, the oxide layer 16 and the P-type Bragg reflector 1113 are both ridge waveguide structures, and only cover a part of the insulating layer 13. An oxide hole 161 is provided on the oxide layer 16, and the oxide hole 161 is used to control the mode and divergence angle of the emitted laser. The N-type electrode layer 14 covers the surface of one side of the insulating layer 13 away from the active layer 1112, and is spaced at the periphery of the P-type Bragg reflector 1113. The P-type electrode layer 15 covers the surface of one side of the P-type Bragg reflector 1113 away from the insulating layer 13.

[0076] When manufacturing the micro-nano structure unit 12, if the material of the micro-nano structure 121 is the same as the material of the substrate 112 (for example, the material of the micro-nano structure 121 and the material of the substrate 112 are both gallium arsenide), no additional coating process is required. Fig.16 As shown in (a) and (b), multiple micro-nano structure units 12 can be directly manufactured on the substrate 112 by photolithography.

[0077] If the material of the micro-nano structure 121 is different from the material of the substrate 112 (for example, the material of the substrate 112 is gallium arsenide, and the material of the micro-nano structure 121 is silicon), then Fig.17As shown in (a) to (b), a micro-nano structure layer 1210 needs to be formed on the first surface 112a of the substrate 112 by a deposition process. Fig.17 As shown in (c), a plurality of micro-nano structure units 12 are formed on the micro-nano structure layer 1210 through a single patterning process. The substrate 112 can be used as a cut-off layer of the micro-nano structure 121, so that the etching depth of the micro-nano structure unit 12 is consistent and the micro-nano structure 121 has high precision.

[0078] In some embodiments of the present application, the patterning process may include a photolithography process, or a photolithography process and an etching step, and may also include other processes such as printing and inkjetting for forming a predetermined pattern; the photolithography process refers to a process for forming a pattern using a photoresist, a mask, an exposure machine, etc., including film formation, exposure, and development processes. The corresponding patterning process can be selected according to the structure formed in the present application. Among them, the one-time patterning process in the embodiments of the present application is explained by taking the example of forming different exposure areas through a mask exposure process, and then performing multiple etching, ashing, and other removal processes on the different exposure areas to finally obtain the expected pattern.

[0079] Example 2

[0080] The laser chip 1 in this example is also a back-emitting vertical cavity surface emitting laser. The hierarchical structure of the laser chip 1 in this example is similar to that in Example 1, except that: Fig.18 As shown, the N-type electrode layer 14 in this example is disposed on the first surface 112 a of the substrate 112 .

[0081] Similarly, when manufacturing the micro-nano structure unit 12, if the material of the micro-nano structure 121 is the same as the material of the substrate 112 (eg, the material of the micro-nano structure 121 and the material of the substrate 112 are both gallium arsenide), no additional coating process is required. Fig.19 As shown in (a) to (b), an N-type electrode layer 14 is first formed on the first surface 112a of the substrate 112. Then, as Fig.19 As shown in (c), a plurality of light outlets 110 may be formed on the N-type electrode layer 14 by a patterning process. Fig.19 As shown in (d), a plurality of micro-nano structure units 12 are directly manufactured on the first surface 112 a of the substrate 112 at the plurality of light outlets 110 by a photolithography process.

[0082] If the material of the micro-nano structure 121 is different from the material of the substrate 112 (for example, the material of the substrate 112 is gallium arsenide, and the material of the micro-nano structure 121 is silicon), then Fig. 20 As shown in (a) to (b), an N-type electrode layer 14 is first formed on the first surface 112a of the substrate 112. Then, as Fig. 20As shown in (c), a plurality of light outlets 110 are formed on the N-type electrode layer 14 by a patterning process. Fig. 20 As shown in (d), a micro-nano structure layer 1210 is formed on the substrate 112 and the N-type electrode layer 14. Fig. 20 As shown in (e), a plurality of micro-nano structure units 12 are formed in the micro-nano structure layer 1210 through a single patterning process. The substrate 112 can also serve as a cut-off layer for the micro-nano structure 121, so that the etching depth of the micro-nano structure unit 12 is consistent and the micro-nano structure 121 has high precision.

[0083] Example 3

[0084] The laser chip 1 in this example is also a front-emitting vertical cavity surface emitting laser. Fig.21 The laser chip 1 includes a substrate 112, a plurality of light emitting units 111, an insulating layer 13, an N-type electrode layer 14, a P-type electrode layer 15, an oxide layer 16 and a plurality of micro-nano structure units 12. The substrate 112 has a first surface 112a and a second surface 112b. The first surface 112a is Fig.21 The upper surface of the substrate 112 shown in FIG. 1 is a second surface 112b. Fig.21 The lower surface of the substrate 112 is shown. A plurality of light emitting units 111 are respectively disposed on the first surface 112 a of the substrate 112 . The N-type electrode layer 14 is disposed on the second surface 112 b of the substrate 112 .

[0085] Any light-emitting unit 111 includes an N-type Bragg reflector 1111, an active layer 1112 and a P-type Bragg reflector 1113, wherein the N-type Bragg reflector 1111, the active layer 1112, the insulating layer 13, the oxide layer 16 and the P-type Bragg reflector 1113 are sequentially stacked on the first surface 112a of the substrate 112. Among them, the oxide layer 16 and the P-type Bragg reflector 1113 are ridge waveguide structures, which only cover a part of the insulating layer 13. An oxide hole 161 is provided in the oxide layer 16, and the oxide hole 161 is used to control the mode and divergence angle of the emitted laser. The light outlets 110 of the plurality of light-emitting units 111 are respectively located on the side surface of the P-type Bragg reflector 1113 away from the insulating layer 13 (i.e. Fig.21 The plurality of micro-nano structure units 12 are respectively located at the light outlets 110 on the upper surfaces of the plurality of P-type Bragg reflectors 1113. The P-type electrode layer 15 covers the upper surface of the P-type Bragg reflector 1113 and is spaced apart at the periphery of the plurality of micro-nano structure units 12.

[0086] When manufacturing the micro-nano structure unit 12, if the material of the micro-nano structure 121 is the same as the material of the top film layer in the P-type Bragg reflector 1113 (for example, the material of the micro-nano structure 121 and the material of the top film layer in the P-type Bragg reflector 1113 are both gallium arsenide), no additional coating process is required. After forming a plurality of light outlets 110 on the P-type electrode layer 15, as shown in FIG. Fig. 22 As shown in (a) to (b), a plurality of micro-nano structure units 12 can be directly manufactured on the topmost film layer of the P-type Bragg reflector 1113 by photolithography.

[0087] If the material of the micro-nano structure 121 is different from the material of the top film layer in the P-type Bragg reflector 1113 (for example, the material of the top film layer in the P-type Bragg reflector 1113 is gallium arsenide, and the material of the micro-nano structure 121 is silicon), after forming a plurality of light outlets 110 on the P-type electrode layer 15, Fig.23 As shown in (a) to (b), a micro-nano structure layer 1210 needs to be formed on the insulating layer 13, the P-type electrode layer 15, and the P-type Bragg reflector 1113 by a deposition process. Fig.23 As shown in (c), a plurality of micro-nano structure units 12 are formed on the micro-nano structure layer 1210 through a single patterning process. The P-type Bragg reflector 1113 can be used as a cutoff layer of the micro-nano structure 121, so that the etching depth of the micro-nano structure unit 12 is consistent and the micro-nano structure 121 has high precision.

[0088] It can be seen from the above examples 1 to 3 that the additional micro-nano structure unit 12 as a beam shaping structure proposed in the embodiment of the present application can be applicable to semiconductor lasers of various structures.

[0089] It should be noted that the laser radar 1000 using the laser chip 1 of the above embodiment can be applied to many fields such as consumer electronics, autonomous driving, augmented reality, virtual reality, robots and drones. Therefore, the embodiment of the present application may also include an electronic device, which may include a mobile phone, a tablet, a television, a laptop, a security camera device, a vehicle-mounted device, augmented reality (AR) glasses, AR helmets, virtual reality (VR) glasses or VR helmets, robots and drones and other devices with lenses. The embodiment of the present application does not impose any special restrictions on the specific form of the above electronic device. The electronic device may include a controller, which may be electrically connected to the above laser radar 1000. Thereby, the detection of the laser radar 1000 is controlled by the controller.

[0090] The above is only a specific implementation of the present application, but the protection scope of the present application is not limited thereto. Any person skilled in the art who is familiar with the present technical field can easily think of changes or substitutions within the technical scope disclosed in the present application, which should be included in the protection scope of the present application. Therefore, the protection scope of the present application should be based on the protection scope of the claims.

Claims

1. A laser chip, It is characterized in that include: A laser module, wherein the laser module comprises a plurality of light-emitting units, wherein the plurality of light-emitting units are distributed in an array; the laser module is formed with a plurality of light-emitting ports arranged at intervals, wherein the plurality of light-emitting ports correspond to the plurality of light-emitting units respectively; and the laser beams emitted by the plurality of light-emitting units are emitted through the plurality of light-emitting ports respectively; A plurality of micro-nano structure units, wherein the plurality of micro-nano structure units are respectively arranged at the plurality of light exits, and one micro-nano structure unit is arranged at any of the light exits; the micro-nano structure unit comprises a plurality of the micro-nano structures distributed at intervals; and among the micro-nano structure units at the plurality of light exits, at least some of the micro-nano structure units have at least one different distribution, quantity and size of the plurality of micro-nano structures.

2. The laser chip according to claim 1, It is characterized in that The laser module further comprises a substrate having a first surface and a second surface opposite to each other; the plurality of light outlets are respectively located on the first surface of the substrate, and the plurality of light emitting units are all located on the second surface.

3. The laser chip according to claim 1, It is characterized in that The laser module further comprises a substrate, and the plurality of light emitting units are all arranged on the same surface of the substrate; the plurality of light exits are respectively arranged on a surface of the plurality of light emitting units on one side away from the substrate.

4. The laser chip according to any one of claims 1 to 3, It is characterized in that The micro-nano structure is in a column shape.

5. The laser chip according to claim 4, It is characterized in that The distance between two adjacent micro-nano structures in the micro-nano structure unit is less than half of the working wavelength of the laser light beam emitted by the corresponding light-emitting unit.

6. The laser chip according to any one of claims 1 to 3, It is characterized in that The micro-nano structure is in a ring shape, and a plurality of the micro-nano structures in the micro-nano structure unit are nested in sequence from the inside to the outside.

7. The laser chip according to claim 6, It is characterized in that The radial period of the micro-nano structure in the micro-nano structure unit is less than half of the working wavelength of the laser light beam emitted by the corresponding light-emitting unit.

8. The laser chip according to any one of claims 1 to 7, It is characterized in that The average extinction coefficient k of the micro-nano structure in the working band is less than or equal to 0.

1.

9. A laser transmitter, It is characterized in that include: The laser chip according to any one of claims 1 to 8; A packaging structure is provided with a mounting cavity formed therein, and the laser chip is mounted in the mounting cavity.

10. A laser radar, It is characterized in that include: Circuit boards; The laser emitter as described in claim 9 is electrically connected to the circuit board.

11. The laser radar according to claim 10, It is characterized in that The circuit board is provided with a laser driving circuit, which is connected to a plurality of light-emitting units of a laser chip in the laser transmitter and is used to control the plurality of light-emitting units to emit light or be turned off.

12. An electronic device, It is characterized in that include: Controller; The laser radar described in claim 10 or 11 above is electrically connected to the controller.

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