Semiconductor laser and laser radar

Abstract

The invention discloses a semiconductor laser and a laser radar, and the laser comprises a semiconductor laminated structure which is divided into two regions. The first area shares a double-heterojunction structure array of a first type doped semiconductor layer, the second area is arranged around the first area and has high insulation and high heat conduction performance, and the thermoelectric refrigeration device is directly arranged on the second area and directly conducts efficient heat dissipation on the double-heterojunction structure array. The transmitting assembly adopts the laser radar of the semiconductor laser, and due to the fact that the transmitting assembly achieves more efficient and more direct heat dissipation, the best working state can be kept in the high-temperature environment.

Description

Technical Field

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

[0002] Vertical-Cavity Surface-Emitting Laser (VCSEL) is an advanced semiconductor laser. Its uniqueness lies in the formation of a resonant cavity in the vertical direction of the substrate and the emission of laser in the vertical direction. VCSEL has significant advantages such as small temperature drift, low threshold, easy fiber coupling, low power consumption and good dynamic single-mode performance. It has shown great potential in application scenarios such as automotive laser radar, face recognition, and 3D sensing.

[0003] However, the working environment of VCSEL in automotive LiDAR is relatively harsh. When the working environment temperature reaches a certain level, the optical power of VCSEL will drop rapidly. This is because the performance of VCSEL deteriorates with the increase of temperature, and its thermal sensitivity makes it difficult to maintain the best working state in a high temperature environment.

[0004] Therefore, how to reduce the operating temperature of VCSEL is an issue that urgently needs attention and resolution. Summary of the invention

[0005] The purpose of this application is to provide a semiconductor laser and a laser radar that can improve the above-mentioned problems.

[0006] The embodiment of the present application is implemented as follows: In a first aspect, the present application provides a semiconductor laser, which includes a semiconductor stacked structure and a thermoelectric cooling device; The semiconductor stacked structure comprises a first region and a second region surrounding the first region, the first region is provided with a double heterojunction structure array sharing a first-type doped semiconductor layer, ion implantation is performed on the second region to form an insulating heat-conducting portion, and the insulating heat-conducting portion is in thermal contact with the double heterojunction structure array; The thermoelectric cooling device is disposed in the second region and is configured to perform energy exchange with the insulating heat-conducting part.

[0007] It can be understood that in the present application, ion implantation is performed on the second region to enhance its thermal conductivity, thereby forming a thermal conductive region, and then a thermoelectric cooling device is directly arranged on the thermal conductive region to dissipate heat. Compared with the prior art in which the thermoelectric cooling device is attached to the back of the substrate where the double heterojunction structure array is located, since the thermoelectric cooling device is closer to each double heterojunction structure that generates heat, the heat dissipation effect is more direct and more significant.

[0008] In an optional embodiment of the present application, at least one channel surrounding the first region is provided in the second region, and the thermoelectric cooling device is provided in the channel, and / or the thermoelectric cooling device is provided outside the channel. It can be understood that after the channel is opened in the second region, the thermoelectric cooling device is provided in the channel, so that the thermoelectric cooling device is closer to the first region generating heat, and the area overlapping with the second region is more, which is more conducive to the heat dissipation effect.

[0009] In an optional embodiment of the present application, the thermoelectric cooling device includes P-type thermoelectric elements and N-type thermoelectric elements alternately arranged along the current direction of the thermoelectric cooling device, and adjacent P-type thermoelectric elements and N-type thermoelectric elements are electrically connected through a conductive heat sink to form a thermocouple structure.

[0010] It can be understood that, taking the N-type thermoelectric element as an example, it may include a first end and a second end that are relatively arranged, and there is a temperature difference between the first end and the second end; the conductive heat sink in contact with the first end is configured to exchange heat with the first end, and the conductive heat sink in contact with the second end is configured to exchange heat with the second end. The situation of the P-type thermoelectric element is the same as that of the N-type thermoelectric element, which will not be repeated here. Furthermore, the DC current passing from the N-type thermoelectric element to the P-type thermoelectric element will cool the conductive heat sink sandwiched between them, and the DC current passing from the P-type thermoelectric element to the N-type thermoelectric element will heat the conductive heat sink sandwiched between them.

[0011] In an optional embodiment of the present application, the thermocouple structures are connected end to end and arranged along the edge contour of the double heterojunction structure array; and / or, the thermocouple structures are connected end to end to cover the second area in a preset path.

[0012] It can be understood that the thermocouple structures are connected end to end and arranged along the edge contour of the double heterojunction structure array, which can reduce the number of thermocouple structures as much as possible under the condition that the thermocouple structures surround the first area for heat dissipation, thereby reducing the cost of the thermoelectric refrigeration device. In addition, the thermocouple structures are connected end to end to cover the second area with a preset path. Although the number of thermocouple structures is increased, the thermocouple structures cover the second area, which improves the heat transfer efficiency of the second area.

[0013] In an optional embodiment of the present application, the thermocouple structure includes: the adjacent P-type thermoelectric element and the N-type thermoelectric element are electrically connected by a conductive heat sink covering the same side surface of the two, forming a first thermocouple structure, wherein the two adjacent conductive heat sinks are arranged on the opposite surfaces of the same thermoelectric element. It can be understood that the above-mentioned first thermocouple structure is a traditional thermocouple structure. The working principle of the traditional thermocouple structure is based on the Seebeck effect, that is, two different thermoelectric elements form a closed loop. When the temperatures of the two junctions are different, an electromotive force is generated in the loop. The magnitude of the electromotive force is related to the temperature difference, and the temperature difference can be determined by measuring the electromotive force. Its technical advantages are significant, the structure is simple, it is composed of two thermoelectric elements and connecting parts, and it is easy to manufacture and install; the measurement range is wide and can adapt to different temperature environments; the response speed is fast, and the temperature change can be quickly sensed; and the stability is good, and the performance can be kept stable in long-term use, providing reliable guarantee for temperature measurement.

[0014] In an optional embodiment of the present application, the thermocouple structure includes: the adjacent P-type thermoelectric element and the N-type thermoelectric element are electrically connected by a conductive heat sink sandwiched between the two to form a second thermocouple structure. It can be understood that compared with the traditional thermocouple structure, the second thermocouple structure uses a smaller-sized thermoelectric element but can achieve the same heat dissipation effect. This improvement allows more thermoelectric elements to be arranged in the same space, thereby significantly improving the heat dissipation density.

[0015] In an optional embodiment of the present application, in the second thermocouple structure, at least one of the conductive heat sinks extends toward the light-emitting body to form a first heat sink; at least one of the conductive heat sinks extends in a direction away from the light-emitting body to form a second heat sink; and two adjacent conductive heat sinks extend in different directions. It can be understood that the conductive heat sink can extend outward in addition to the area in contact with the thermoelectric element. Whether it extends toward the light-emitting body or in a direction away from the light-emitting body, the heat dissipation area of ​​the conductive heat sink can be increased, thereby achieving a better heat dissipation effect. In addition, the extension of two adjacent conductive heat sinks in different directions can avoid the extension parts of the two adjacent conductive heat sinks from restricting each other on the same side and blocking each other's extension size. The scheme of extending the upper and lower layers separately can make more full use of the space and achieve the effect of maximizing the extension area.

[0016] In an optional embodiment of the present application, in the second thermocouple structure, the P-type thermoelectric element and / or the N-type thermoelectric element are deposited on the first-type doped semiconductor layer by a vapor deposition process. It can be understood that the P-type thermoelectric element and / or the N-type thermoelectric element are prepared on the first-type doped semiconductor layer by a vapor deposition process, which enhances the combination stability of the thermoelectric cooling device and the double heterojunction structure.

[0017] In an optional embodiment of the present application, the thermoelectric cooling device further includes at least one protective plate, the protective plate covers the second thermocouple structure and / or the first thermocouple structure, and the protective plate is bonded to the second region by gold-gold bonding. It can be understood that the protective plate can, on the one hand, play a certain packaging and protection role for each thermocouple structure, and on the other hand, can be fixed to the first type doped semiconductor layer by gold-gold bonding, thereby enhancing the bonding stability between the thermoelectric cooling device and the double heterojunction structure.

[0018] In an optional embodiment of the present application, the double heterojunction structure array is grown on a substrate layer; each double heterojunction structure includes a stacked first-type doped semiconductor layer, an active layer, and a second-type doped semiconductor layer, and a second chip electrode is arranged on the second-type doped semiconductor layer; a first chip electrode is arranged on the side of the substrate layer away from the double heterojunction structure array, and the first chip electrode is connected to the first-type doped semiconductor layer through the substrate layer.

[0019] In an optional embodiment of the present application, in the double heterojunction structure, a confinement ring is provided on a side of the active layer close to the first-type doped semiconductor layer and / or a side close to the second-type doped semiconductor layer, and the confinement ring is arranged around the light emitting area of ​​the active layer and is configured to limit the current conduction of the double heterojunction structure.

[0020] In an optional embodiment of the present application, the first-type doped semiconductor layer is a semiconductor layer doped with a Group V element / Group III element, and the second-type doped semiconductor layer is a semiconductor layer doped with a Group III element / Group V element; The ion implantation material of the second region includes at least one of the following substances: H + , O ⁺ , N⁺, Ar⁺.

[0021] In an optional embodiment of the present application, the channel located in the second region sequentially penetrates the second-type doped semiconductor layer and the active layer, and exposes a portion of the surface of the first-type doped semiconductor layer.

[0022] In an optional embodiment of the present application, the thermoelectric cooling device is arranged on a side of the second type doped semiconductor layer in the second region away from the substrate layer; and / or the thermoelectric cooling device is located on a light emitting direction side of the double heterojunction structure array.

[0023] In an optional embodiment of the present application, the double heterojunction structure array includes at least one of the following: At least two double heterojunction structures arranged in an axisymmetric or centrosymmetric manner; Seven double heterojunction structures are arranged in an axisymmetric or centrosymmetric manner.

[0024] In an optional embodiment of the present application, the edge profile of the double heterojunction structure array includes at least one of the following: The edge profile of the double heterojunction structure array is an axisymmetric polygon; The edge profile of the double heterojunction structure array is a centrally symmetrical polygon.

[0025] It can be understood that the double heterojunction structure array is arranged in an axisymmetric or centrosymmetric manner, which is conducive to uniform heat dissipation of each double heterojunction structure therein.

[0026] In the second aspect, the present application provides a laser radar, including a transmitting component and a receiving component; the transmitting component adopts a semiconductor laser as described in any one of the first aspects above. It can be understood that the transmitting component of the laser radar adopts the above-mentioned semiconductor laser, and by directly setting a thermoelectric cooling device in the semiconductor layer area with high thermal conductivity, the transmitting component of the laser radar achieves more efficient and direct heat dissipation, so that it can maintain the best working state under high temperature or harsh environment. This design not only improves the performance stability of the laser radar, but also helps to extend its service life. Therefore, the laser radar of the present application shows higher reliability and better performance in application scenarios such as vehicle-mounted, face recognition, and 3D sensing. Beneficial Effects

[0027] The present application proposes a semiconductor laser, which includes a semiconductor stacking structure, which is subdivided into two regions, namely, a first region constituting a double heterojunction structure array that shares a first-type doped semiconductor layer and a surrounding second region with a higher ion implantation concentration and different doping substances. The high ion implantation concentration makes the second region have better thermal conductivity, and the thermoelectric cooling device is directly arranged on this second region with high thermal conductivity to directly and efficiently dissipate heat from the double heterojunction structure array. Compared with the prior art in which the thermoelectric cooling device is attached to the back of the substrate where the double heterojunction structure array is located, the present application achieves more direct and more effective heat dissipation by directly arranging the thermoelectric cooling device in the second region with a high doping concentration. This design not only improves the heat dissipation efficiency, but also helps to maintain the optimal working state of the semiconductor laser, especially in high temperature or harsh environments.

[0028] The present application also provides a laser radar, including a transmitting component and a receiving component; the transmitting component adopts the semiconductor laser as described above. It can be understood that the transmitting component of the laser radar adopts the above-mentioned semiconductor laser, and by directly setting a thermoelectric cooling device in the semiconductor layer area with high thermal conductivity, the transmitting component of the laser radar achieves more efficient and direct heat dissipation, so that it can maintain the best working state under high temperature or harsh environment. This design not only improves the performance stability of the laser radar, but also helps to extend its service life. Therefore, the laser radar of the present application shows higher reliability and better performance in application scenarios such as vehicle-mounted, face recognition, and 3D sensing.

[0029] In order to make the above-mentioned objects, features and advantages of the present application more obvious and understandable, optional embodiments are specifically listed below and described in detail with reference to the attached drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the drawings required for use in the embodiments will be briefly introduced below. It should be understood that the following drawings only show certain embodiments of the present application and therefore should not be regarded as limiting the scope. For ordinary technicians in this field, other related drawings can be obtained based on these drawings without paying creative work.

[0031] Figure 1 is a top view of a semiconductor laser provided by the present application; Figure 2 yes Figure 1 An AA' cross-sectional view of the semiconductor laser shown; Figure 3 yes Figure 1 Another AA' cross-sectional view of the semiconductor laser shown; Figure 4 is a top view of another semiconductor laser provided by the present application; Figure 5 is a cross-sectional schematic diagram of a first thermocouple structure provided in the present application; Figure 6 is a cross-sectional schematic diagram of a second thermocouple structure provided by the present application; Figure 7 is a cross-sectional schematic diagram of another thermocouple structure provided by the present application; Figure 8 is a schematic diagram of a first thermocouple structure; Fig. 9 is a schematic diagram of the second thermocouple structure. DETAILED DESCRIPTION

[0032] The following will be combined with the drawings in the embodiments of the present application to clearly and completely describe the technical solutions in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of this application.

[0033] First, as Figure 1 and Figure 2 As shown, the present application provides a semiconductor laser, which includes a semiconductor stacked structure and a thermoelectric cooling device 20.

[0034] like Figure 1 As shown, the semiconductor stacked structure includes a first region 311 and a second region 312 surrounding the first region 311, the first region 311 constitutes a double heterojunction structure array sharing a first-type doped semiconductor layer 31, the second region 312 is ion implanted to form an insulating heat-conducting portion (refer to 312), and the insulating heat-conducting portion is in thermal contact with the double heterojunction structure array. The thermal contact can be interpreted as the two having direct physical contact or connection relationship, or it can be interpreted as the two having no direct physical contact or connection relationship.

[0035] The thermoelectric cooling device 20 is arranged in the second area 312 and is configured to perform energy exchange with the insulating heat-conducting part. The energy exchange mainly refers to exchanging the heat in the insulating heat-conducting part through the thermoelectric cooling device 20, or transferring the heat to the insulating heat-conducting part through the thermoelectric cooling device. In this way, dynamic control of heating and cooling can be achieved according to the specific working conditions of the device.

[0036] In an optional embodiment of the present application, the double heterojunction structure array includes at least one of the following: at least two double heterojunction structures arranged in an axisymmetric or centrosymmetric manner; or seven double heterojunction structures arranged in an axisymmetric or centrosymmetric manner.

[0037] like Figure 1 As shown, Figure 1 The double heterojunction structure array 10 includes 7 double heterojunction structures arranged symmetrically in the center, namely, a first double heterojunction structure 11, a second double heterojunction structure 12, a third double heterojunction structure 13, a fourth double heterojunction structure 14, a fifth double heterojunction structure 15, a sixth double heterojunction structure 16, and a seventh double heterojunction structure 17. The first double heterojunction structure 11 is arranged at the center, and the other 6 double heterojunction structures surround the first double heterojunction structure 11.

[0038] It can be understood that in the present application, ion implantation is performed on the second region 312 to form an insulating heat-conducting portion, so that the thermal conductivity of the region becomes stronger, forming a heat-conducting region, and then a thermoelectric cooling device 20 is directly arranged on the heat-conducting region for heat dissipation. Compared with the prior art in which the thermoelectric cooling device 20 is attached to the back side of the substrate where the double heterojunction structure array 10 is located, since the thermoelectric cooling device 20 is closer to each double heterojunction structure that generates heat, the heat dissipation effect is more direct and more significant.

[0039] refer to Figure 2 , the double heterojunction structure array 10 is grown on the substrate layer 32; each double heterojunction structure includes a first type doped semiconductor layer 31, an active layer 33 and a second type doped semiconductor layer 34 which are stacked to form a PN junction. When the carriers in the P region and the N region are injected into the active layer 33 under the action of the external circuit, the electrons and holes recombine in the active layer 33, release energy and generate photons. Since the cavity of the VCSEL is vertical, the photons are reflected multiple times between the reflectors formed by the two layers of doped semiconductor layers and are stimulated to be amplified to form coherent light. A second chip electrode 35 is arranged on the second type doped semiconductor layer 34; a first chip electrode 36 is arranged on the side of the substrate layer 32 away from the double heterojunction structure array 10, and the first chip electrode 36 is connected to the first type doped semiconductor layer 31 through the substrate layer 32. The first chip electrode 36 and the second chip electrode 35 are configured to apply a voltage to drive the injection of carriers and stimulate photon emission.

[0040] In an optional embodiment of the present application, the first-type doped semiconductor layer 31 may be a semiconductor layer doped with group V elements / group III elements, and the second-type doped semiconductor layer 34 may be a semiconductor layer doped with group III elements / group V elements, and the doping types of the first-type doped semiconductor layer 31 and the second-type doped semiconductor layer 34 are opposite. Exemplarily, the first-type doped semiconductor layer 31 may be doped with group V elements to form an N-type semiconductor layer, and the second-type doped semiconductor layer 34 may be doped with group III elements to form a P-type doped semiconductor layer. The base layer of the N-type doped semiconductor layer is usually made of semiconductor materials such as silicon (Si), germanium (Ge) or gallium arsenide (GaAs), in which pentavalent elements such as phosphorus (P), arsenic (As) or antimony (Sb) are doped as dopants. These dopants can provide additional electrons, so that the electron concentration in the N-type semiconductor is much higher than the hole concentration. The base layer of the P-type doped semiconductor layer is made of the same semiconductor substrate, such as silicon, germanium or gallium arsenide, but doped with trivalent elements such as boron (B), aluminum (Al) or gallium (Ga). These dopants generate holes in the semiconductor lattice, making the hole concentration in the P-type semiconductor higher than the electron concentration. The combination of N-type and P-type semiconductors forms a PN junction, which is the core structure of optoelectronic devices such as VCSEL. The second region 312 can have the same basic structure as the first region 311, for example, both include a first-type doped semiconductor layer 31, an active layer 33, and a second-type doped semiconductor layer 34. This method is the easiest to manufacture, that is, it is made on the same epitaxial wafer. The difference is that the second region 312 is additionally subjected to one or more ion implantation processes to form an insulating heat-conducting portion including a high concentration of implanted ions. The specific implanted substances and doses will be described later.

[0041] In an optional embodiment of the present application, the optional ion implantation material may be H + , O ⁺ At least one of N⁺, Ar⁺, exemplarily, H + For example, ion implantation can be performed at a dose of ≥1×10¹ 7 ions / cm², and the energy is 150 keV. The implantation methods of other substances are similar. It can be understood that the method of achieving insulation and heat conduction by ion implantation can be understood by referring to the prior art. This application has no special improvement on this part of the process, so it will not be further described here.

[0042] In the optional embodiments of the present application, reference may be made to Figure 3 The channel 40 located in the second region 312 sequentially penetrates the second type doped semiconductor layer 34 and the active layer 33, and exposes a portion of the surface of the first type doped semiconductor layer 31. When manufacturing the channel 40, an ion implantation process may be performed first, then a channel etching may be performed, and then the thermoelectric cooling device 20 may be manufactured; or an ion implantation process may be performed first, then the thermoelectric cooling device 20 may be manufactured, and finally the channel etching may be performed.

[0043] like Figure 2 As shown, the thermoelectric cooling device 20 is disposed on a side of the second type doped semiconductor layer 34 in the second region 312 away from the substrate layer 32 , and / or the thermoelectric cooling device 20 is located on a light emitting direction side of the double heterojunction structure array.

[0044] Continue to refer Figure 2 In the double heterojunction structure, a limiting ring 37 is provided on one side of the active layer 33 close to the second type doped semiconductor layer 34. The limiting ring 37 is provided around the light emitting area of ​​the active layer 33 and is configured to limit the current conduction of the double heterojunction structure. After the double heterojunction structure is turned on, the current is limited by the limiting ring 37 and is finally introduced into the light emitting area of ​​the double heterojunction structure, so that the light emitting area of ​​the double heterojunction structure generates laser. More specifically, in the embodiment of the present application, the limiting ring 37 has a limiting area surrounding the light emitting area, the limiting area has a higher resistivity to limit the carriers from flowing into the middle area of ​​the double heterojunction structure, and the refractive index of the limiting area is lower to laterally limit the photons. The carrier and optical lateral confinement increases the density of carriers and photons in the active layer 33, and improves the efficiency of generating light in the active layer 33. Optionally, the above-mentioned limiting ring 37 can also be provided on one side of the active layer 33 close to the first type doped semiconductor layer 31, which will not be described in detail here.

[0045] like Figure 3 As shown, at least one channel 40 surrounding the first region 311 is disposed in the second region 312 .

[0046] like Figure 3 As shown, the thermoelectric cooling device 20 is disposed in the channel 40. It can be understood that after the channel 40 is opened in the second area 312, the thermoelectric cooling device 20 is disposed in the channel 40, so that the thermoelectric cooling device 20 is closer to the first area 311 where heat is generated, and the area overlapping with the second area 312 is more, which is more conducive to the heat dissipation effect. Optionally, the thermoelectric cooling device 20 is also disposed outside the channel 40, which will not be repeated here.

[0047] The thermoelectric cooling device includes P-type thermoelectric elements and N-type thermoelectric elements arranged alternately along the current direction of the thermoelectric cooling device, and adjacent P-type thermoelectric elements and N-type thermoelectric elements are electrically connected through a conductive heat sink to form a thermocouple structure. It can be understood that, taking the N-type thermoelectric element as an example, it may include a first end and a second end arranged opposite to each other, and there is a temperature difference between the first end and the second end; the conductive heat sink in contact with the first end is configured to perform heat exchange with the first end, and the conductive heat sink in contact with the second end is configured to perform heat exchange with the second end. The situation of the P-type thermoelectric element is the same as that of the N-type thermoelectric element, which will not be repeated here. Furthermore, the DC current passing from the N-type thermoelectric element to the P-type thermoelectric element will cool the conductive heat sink sandwiched between them, and the DC current passing from the P-type thermoelectric element to the N-type thermoelectric element will heat the conductive heat sink sandwiched between them.

[0048] The above-mentioned alternating arrangement means that the thermoelectric element combinations of the same structure are arranged in sequence in the current direction of the thermoelectric cooling device, and in these thermoelectric element combinations, the arrangement form of the P-type thermoelectric element and the N-type thermoelectric element is the same. That is, along the current direction of the thermoelectric cooling device, the P-type thermoelectric element is arranged first, and then the N-type thermoelectric element is arranged; or, along the current direction of the thermoelectric cooling device, the N-type thermoelectric element is arranged first, and then the P-type thermoelectric element is arranged.

[0049] Optionally, the conductive heat sink may be made of copper or aluminum with good thermal conductivity and good electrical conductivity to facilitate the attachment of thermoelectric materials and the flow of current at low resistance. The thermoelectric material may be manganese silicide compounds (Mn-Si), magnesium silicide compounds (Mg-Si-Sn), skutterudite compounds (Co-Sb), half-Heusler compounds (Zr-Ni-Sn) and bismuth telluride compounds (Bi-Te).

[0050] In an optional embodiment of the present application, if Figure 1 As shown, the thermocouple structures are arranged end to end along the edge contour of the double heterojunction structure array 10. It can be understood that the thermocouple structures are arranged end to end along the edge contour of the double heterojunction structure array 10, which can reduce the number of thermocouple structures as much as possible while satisfying the condition that the thermocouple structures surround the first area 311 for heat dissipation, thereby reducing the cost of the thermoelectric cooling device 20.

[0051] In an optional embodiment of the present application, if Figure 4As shown, the thermocouple structures are connected end to end to cover the second area 312 with a Z-shaped preset path. Optionally, in addition to the Z-shaped path, the preset path may also include other path solutions that can cover the second area, such as a circuitous path, which will not be repeated here. It can be understood that the thermocouple structures are connected end to end to cover the second area 312 with a preset path. Although the number of thermocouple structures is increased, the thermocouple structures cover the second area 312, which improves the heat transfer efficiency of the second area 312.

[0052] In an optional embodiment of the present application, the edge profile of the double heterojunction structure array includes at least one of the following: The edge profile of the double heterojunction structure array is an axisymmetric polygon; The edge profile of the double heterojunction structure array is a centrally symmetric polygon.

[0053] It can be understood that the double heterojunction structure array is arranged in an axisymmetric or centrosymmetric manner, which is conducive to uniform heat dissipation of each double heterojunction structure therein.

[0054] In an optional embodiment of the present application, the thermocouple structure includes: adjacent P-type thermoelectric elements and N-type thermoelectric elements are electrically connected through a conductive heat sink covering the same side surface of the two elements, forming a first thermocouple structure, wherein the two adjacent conductive heat sinks are arranged on opposite surfaces of the same thermoelectric element. Figure 5 As shown, the first N-type thermoelectric element 51 is electrically connected to the first P-type thermoelectric element 71 on the left side through the first conductive heat sink 61 covering the top surface; the first N-type thermoelectric element 51 is electrically connected to the other P-type thermoelectric elements on the right side through the second conductive heat sink 62 covering the bottom surface; the first P-type thermoelectric element 71 is electrically connected to the other N-type thermoelectric elements on the left side through the third conductive heat sink 63 covering the bottom surface. It can be understood that the above-mentioned first thermocouple structure is a traditional thermocouple structure. The working principle of the traditional thermocouple structure is based on the Seebeck effect, that is, two different thermoelectric elements form a closed loop. When the temperatures of the two junctions are different, an electromotive force is generated in the loop. The magnitude of the electromotive force is related to the temperature difference. The temperature difference can be determined by measuring the electromotive force. Its technical advantages are significant, the structure is simple, it is composed of two thermoelectric elements and connecting parts, and it is easy to manufacture and install; the measurement range is wide and can adapt to different temperature environments; the response speed is fast, and the temperature change can be quickly sensed; and the stability is good. It can maintain stable performance in long-term use, providing reliable guarantee for temperature measurement.

[0055] In an optional embodiment of the present application, the thermocouple structure includes: adjacent P-type thermoelectric elements and N-type thermoelectric elements are electrically connected via a conductive heat sink sandwiched between the two, forming a second thermocouple structure. The above-mentioned sandwiching means that the conductive heat sink is disposed between the P-type thermoelectric element and the N-type thermoelectric element. Specifically, the conductive heat sink is physically connected to the P-type thermoelectric element and electrically connected to the first surface of the adjacent P-type thermoelectric element; the conductive heat sink is physically connected to the N-type thermoelectric element and electrically connected to the second surface of the adjacent N-type thermoelectric element. Figure 6 As shown, the second N-type thermoelectric element 52 is electrically connected to the second P-type thermoelectric element 72 through the fourth conductive heat sink 64 sandwiched between the two; the second N-type thermoelectric element 52 is electrically connected to the other P-type thermoelectric element on the right through the fifth conductive heat sink 65 sandwiched between the two; the second P-type thermoelectric element 72 is electrically connected to the other N-type thermoelectric element on the left through the sixth conductive heat sink 66 sandwiched between the two. It can be understood that compared with the traditional thermocouple structure, the second thermocouple structure uses a smaller-sized thermoelectric element, but can achieve the same heat dissipation effect. This improvement allows more thermoelectric elements to be arranged in the same space, thereby significantly improving the heat dissipation density.

[0056] In an optional embodiment of the present application, in the second thermocouple structure, at least one conductive heat sink extends toward the light-emitting body to form a first heat sink; at least one conductive heat sink extends in a direction away from the light-emitting body to form a second heat sink; two adjacent conductive heat sinks extend in different directions. Figure 7 As shown, the fourth conductive heat sink 64 between the second N-type thermoelectric element 52 and the second P-type thermoelectric element 72 extends toward the first direction to form a first heat sink 81; the adjacent fifth conductive heat sink 65 and the sixth conductive heat sink 66 extend in the opposite direction of the first direction to form a second heat sink 82. It can be understood that the conductive heat sink can extend outward in addition to the area in contact with the thermoelectric element. Whether it extends toward the light-emitting body or extends in a direction away from the light-emitting body, the heat dissipation area of ​​the conductive heat sink can be increased, thereby achieving a better heat dissipation effect. In addition, the extension of two adjacent conductive heat sinks in different directions can avoid the extension parts of the two adjacent conductive heat sinks from restricting each other on the same side and blocking each other's extension size. The scheme of extending the upper and lower layers separately can make more full use of the space and achieve the effect of maximizing the extension area.

[0057] Optional, such as Figure 7 , the insulating material 90 is filled between adjacent conductive heat sinks, between the conductive heat sink and the P-type thermoelectric element, and between the conductive heat sink and the N-type thermoelectric element. It can be understood that the filling of the insulating material avoids the poor conduction of each element in the thermoelectric cooling device, ensuring that the thermoelectric cooling device does not have a short circuit failure and maintains normal operation.

[0058] Optionally, the thermoelectric cooling device also includes a first protective plate and a second protective plate; the insulating material is an insulating glue with adhesiveness, the first protective plate is covered on the first side of each thermocouple structure by the insulating glue, and the second protective plate is covered on the second side of each thermocouple structure by the insulating glue, and the first side is opposite to the second side.

[0059] In an optional embodiment of the present application, in the second thermocouple structure, the P-type thermoelectric element and / or the N-type thermoelectric element are deposited on the first-type doped semiconductor layer 31 by a vapor deposition process. It can be understood that the P-type thermoelectric element and / or the N-type thermoelectric element are prepared on the first-type doped semiconductor layer 31 by a vapor deposition process, which enhances the bonding stability of the thermoelectric cooling device 20 and the double heterojunction structure.

[0060] In the preparation process related to the present application, manganese silicide (MnSi) is prepared on a carrier by a vapor deposition process, especially a metal organic chemical vapor deposition (MOCVD) method. Specifically, Mn(CO)5(SiCl3) is used as a single source precursor, and a deposition reaction is carried out on the surface of a silica carrier at 400°C and atmospheric pressure. This process is similar to the way in which a P-type thermoelectric element and / or an N-type thermoelectric element is deposited on a semiconductor layer by a vapor deposition process, which enhances the bonding stability of the deposit (i.e., MnSi nanoparticles supported by silica) and the carrier (silicon dioxide). The final MnSi nanoparticles are about 5-6nm in size and are evenly dispersed on the silica carrier, forming a manganese silicide layer whose thickness may be in the nanoscale range (although not directly specified, it can be inferred from the size of the nanoparticles that the thickness of the layer it constitutes may be in the conventional vapor deposition layer thickness range of 0.5~10μm, which needs to be determined according to the actual deposition conditions).

[0061] In an optional embodiment of the present application, the thermoelectric cooling device 20 further includes at least one protective plate, the protective plate covers the second thermocouple structure and / or the first thermocouple structure, and the protective plate is bonded to the second region by gold-gold bonding. It can be understood that the protective plate can, on the one hand, play a certain packaging and protection role for each thermocouple structure, and on the other hand, can also be fixed to the first type doped semiconductor layer 31 by gold-gold bonding, thereby enhancing the bonding stability between the thermoelectric cooling device 20 and the double heterojunction structure.

[0062] In the conventional first thermocouple structure, adjacent P-type thermoelectric elements and N-type thermoelectric elements are electrically connected via a conductive heat sink covering the top surface. Figure 8 This is a schematic diagram of the structure of a traditional thermocouple. When it is at the best cooling thermal power, the resistance of the conductive heat sink satisfies the following formula: ,in, represents the resistance of the conductive heat sink, i.e. the parasitic resistance, Represents the distance between the P-type thermoelectric element and the N-type thermoelectric element, Represents the length of the overlapped area between the P-type thermoelectric element or the N-type thermoelectric element and the conductive heat sink. Represents the width value of P-type thermoelectric element, N-type thermoelectric element, and conductive heat sink. represents the thickness of the conductive heat sink, Represents the thickness of P-type thermoelectric element and N-type thermoelectric element, Represents the resistivity of the conductive heat sink. When it is at its optimal cooling thermal power, the resistance of the P-type / N-type thermoelectric element satisfies the following formula: ,in, Represents the resistance of the P-type / N-type thermoelectric element, represents the resistivity of the P-type / N-type thermoelectric element. Therefore, Figure 8 The ratio of parasitic resistance to the resistance loss of the thermoelectric element in the thermocouple structure shown Satisfy the following formula: .

[0063] like Fig. 9 For the second thermocouple structure shown, when it is at the best cooling thermal power, the resistance of the conductive heat sink satisfies the following formula: ,in, represents the resistance of the conductive heat sink, i.e. the parasitic resistance, represents the thickness of the conductive heat sink, Represents the length value of P-type thermoelectric element and N-type thermoelectric element, Represents the width value of P-type thermoelectric element, N-type thermoelectric element, and conductive heat sink. Represents the thickness of P-type thermoelectric element and N-type thermoelectric element, Represents the resistivity of the conductive heat sink. When it is at its optimal cooling thermal power, the resistance of the P-type / N-type thermoelectric element satisfies the following formula: ,in, Represents the resistance of the P-type / N-type thermoelectric element, represents the resistivity of the P-type / N-type thermoelectric element. Therefore, Fig. 9 The ratio of parasitic resistance to the resistance loss of the thermoelectric element in the thermocouple structure shown Satisfy the following formula: .

[0064] exist Figure 8 and Fig. 9 When the material parameters of the P-type thermoelectric element, N-type thermoelectric element, and conductive heat sink are consistent, the same resistance loss ratio should be maintained, that is, , the thickness of the thermoelectric element needs to meet the following conditions: Generally speaking, Figure 8 In , The value will be The value is designed to be larger, while limiting Fig. 9 In The value is less than the preset threshold, that is, less than value, in satisfying Under the conditions, .for Figure 8 and Fig. 9 The thermocouple structures shown can all achieve the same optimal cooling thermal power, which requires the following equation to be satisfied: ,because ,therefore , then it is understandable, Fig. 9 The volume of the thermoelectric element in the second thermocouple structure shown will be less than Figure 3 The volume of the thermoelectric element in the traditional thermocouple structure shown ,Right now It can be seen that the use of Fig. 9 With the second thermocouple structure, a smaller thermoelectric element can achieve the same heat dissipation effect as the large thermoelectric element in the traditional thermocouple structure. Fig. 9 The second thermocouple structure can arrange more thermoelectric elements in the same space, thereby improving the heat dissipation density.

[0065] In the second thermocouple structure, the dimension of the conductive heat sink along the current direction is the thickness of the conductive heat sink, and the thickness of the conductive heat sink is less than a preset threshold. It can be understood that in conventional thermocouple structures, the dimensions of the P-type thermoelectric element and the N-type thermoelectric element are the same, and the thickness of the conductive heat sink is generally set to be smaller, that is, smaller than the side length of the cross section of the thermoelectric element perpendicular to the current direction. This can further ensure that the thermocouple structure provided by the present application can achieve the heat dissipation effect achieved by the large-sized thermoelectric element in the traditional thermocouple structure with a smaller-sized thermoelectric element. That is, the above-mentioned preset threshold can be set to the minimum value of the above-mentioned cross-sectional side length, such as Fig. 9 As shown, the above preset threshold can be set to be less than value.

[0066] The expressions "first", "second", "the first" or "the second" used in various embodiments of the present disclosure may modify various components regardless of order and / or importance, but these expressions do not limit the corresponding components. The above expressions are only configured for the purpose of distinguishing an element from other elements. For example, a first user device and a second user device represent different user devices, although both are user devices. For example, a first element may be referred to as a second element, and similarly, a second element may be referred to as a first element without departing from the scope of the present disclosure.

[0067] When one element (e.g., a first element) is referred to as being "(operably or communicatively) coupled" or "(operably or communicatively) coupled to" or "connected to" another element (e.g., a second element), it is understood that the one element is directly connected to the other element or the one element is indirectly connected to the other element via yet another element (e.g., a third element). Conversely, it is understood that when an element (e.g., a first element) is referred to as being "directly connected" or "directly coupled" to another element (the second element), no element (e.g., a third element) is interposed between the two.

[0068] It should be noted that, in this article, the terms "include", "comprises" or any other variants thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements includes not only those elements, but also includes other elements not explicitly listed, or also includes elements inherent to such process, method, article or device. In the absence of further restrictions, an element defined by the sentence "includes a ..." does not exclude the existence of other identical elements in the process, method, article or device including the element. In addition, components, features, and elements with the same name in different embodiments of the present application may have the same meaning or different meanings, and their specific meanings need to be determined by their explanation in the specific embodiment or further combined with the context of the specific embodiment.

[0069] The above description is only an optional embodiment of the present application and an explanation of the technical principles used. Those skilled in the art should understand that the scope of the invention involved in the present application is not limited to the technical solution formed by a specific combination of the above technical features, but should also cover other technical solutions formed by any combination of the above technical features or their equivalent features without departing from the above invention concept. For example, the above features are replaced with the technical features with similar functions disclosed in this application (but not limited to) by each other.

[0070] As used herein, the words "if" and "if" may be interpreted as "at the time of" or "when" or "in response to determining" or "in response to detecting", depending on the context. Similarly, the phrases "if it is determined" or "if (stated condition or event) is detected" may be interpreted as "when it is determined" or "in response to determining" or "when detecting (stated condition or event)" or "in response to detecting (stated condition or event)", depending on the context.

[0071] The above description is only an optional embodiment of the present application and an explanation of the technical principles used. Those skilled in the art should understand that the scope of the invention involved in the present application is not limited to the technical solution formed by a specific combination of the above technical features, but should also cover other technical solutions formed by any combination of the above technical features or their equivalent features without departing from the above invention concept. For example, the above features are replaced with the technical features with similar functions disclosed in this application (but not limited to) by each other.

[0072] The above description is only an optional embodiment of the present application and is not intended to limit the present application. For those skilled in the art, the present application may have various modifications and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present application shall be included in the protection scope of the present application.

Claims

1. A semiconductor laser, characterized in that: Including semiconductor stacked structures and thermoelectric cooling devices; The semiconductor stacked structure comprises a first region and a second region surrounding the first region, the first region is provided with a double heterojunction structure array sharing a first-type doped semiconductor layer, ion implantation is performed on the second region to form an insulating heat-conducting portion, and the insulating heat-conducting portion is in thermal contact with the double heterojunction structure array; The thermoelectric cooling device is disposed in the second region and is configured to perform energy exchange with the insulating heat-conducting part.

2. The semiconductor laser according to claim 1, characterized in that At least one channel surrounding the first region is disposed in the second region, and the thermoelectric cooling device is disposed in the channel, and / or the thermoelectric cooling device is disposed outside the channel.

3. The semiconductor laser according to claim 1, characterized in that The thermoelectric cooling device includes P-type thermoelectric elements and N-type thermoelectric elements alternately arranged along the current direction of the thermoelectric cooling device, and adjacent P-type thermoelectric elements and N-type thermoelectric elements are electrically connected through a conductive heat sink to form a thermocouple structure.

4. The semiconductor laser according to claim 3, characterized in that The thermocouple structures are connected end to end and arranged along the edge contour of the double heterojunction structure array; and / or, the thermocouple structures are connected end to end and spread over the second area in a preset path.

5. The semiconductor laser according to claim 3, characterized in that The thermocouple structure includes at least one of the following: The adjacent P-type thermoelectric elements and the adjacent N-type thermoelectric elements are electrically connected via a conductive heat sink covering the same side surfaces of the two elements, thereby forming a first thermocouple structure, wherein the two adjacent conductive heat sinks are arranged on opposite surfaces of the same thermoelectric element; The adjacent P-type thermoelectric elements and the adjacent N-type thermoelectric elements are electrically connected via a conductive heat sink sandwiched between the two to form a second thermocouple structure.

6. The semiconductor laser according to claim 5, characterized in that In the second thermocouple structure, at least one of the conductive heat sinks extends toward the light-emitting body to form a first heat sink; at least one of the conductive heat sinks extends in a direction away from the light-emitting body to form a second heat sink; and two adjacent conductive heat sinks extend in different directions.

7. The semiconductor laser according to claim 5, characterized in that In the second thermocouple structure, the P-type thermoelectric element and / or the N-type thermoelectric element is deposited on the first-type doped semiconductor layer by a vapor deposition process.

8. The semiconductor laser according to claim 5, characterized in that The thermoelectric cooling device further includes at least one protective plate, the protective plate covers the second thermocouple structure and / or the first thermocouple structure, and the protective plate is bonded to the second region by gold-gold bonding.

9. The semiconductor laser according to claim 2, characterized in that: The double heterojunction structure array is grown on the substrate layer, each double heterojunction structure comprises the first-type doped semiconductor layer, the active layer and the second-type doped semiconductor layer which are stacked, and the second chip electrode is arranged on the second-type doped semiconductor layer; A first chip electrode is disposed on a side of the substrate layer away from the double heterojunction structure array, and the first chip electrode is connected to the first type doped semiconductor layer through the substrate layer.

10. The semiconductor laser according to claim 9, characterized in that The first-type doped semiconductor layer is a semiconductor layer doped with a Group V element / a Group III element, and the second-type doped semiconductor layer is a semiconductor layer doped with a Group III element / a Group V element; The ion implantation material of the second region includes at least one of the following substances: H + 、Oh ⁺ 、N⁺、Ar⁺。 11. The semiconductor laser according to claim 10, characterized in that The channel located in the second region sequentially penetrates the second-type doped semiconductor layer and the active layer, and exposes a portion of the surface of the first-type doped semiconductor layer.

12. The semiconductor laser according to claim 10, characterized in that The thermoelectric cooling device is arranged on a side of the second type doped semiconductor layer in the second region away from the substrate layer; and / or, The thermoelectric cooling device is located on one side of the double heterojunction structure array in the light emitting direction.

13. The semiconductor laser according to any one of claims 1 to 12, characterized in that: The double heterojunction structure array comprises at least one of the following: At least two double heterojunction structures arranged in an axisymmetric or centrosymmetric manner; Seven double heterojunction structures are arranged in an axisymmetric or centrosymmetric manner.

14. The semiconductor laser according to claim 13, characterized in that The edge profile of the double heterojunction structure array includes at least one of the following: The edge profile of the double heterojunction structure array is an axisymmetric polygon; The edge profile of the double heterojunction structure array is a centrally symmetrical polygon.

15. A laser radar, characterized in that: It comprises a transmitting component and a receiving component; the transmitting component adopts the semiconductor laser as described in any one of claims 1-14.

Images