Multi-chip laser array welding device and method

Abstract

The invention provides a multi-chip laser array welding device and method, and relates to the technical field of semiconductor lasers, and the device comprises a base which is used for placing a to-be-welded laser array; the front-end positioning block is used for positioning a laser array to be welded from one end of the front-end positioning block; the rear end positioning block is used for being matched with the front end positioning block and positioning the laser array to be welded from the other end; the side baffle positioning block is used for positioning the laser array to be welded from two sides; the array pressing block is used for positioning the laser array to be welded from the upper end; wherein the laser array to be welded comprises semiconductor laser chips and tungsten copper heat sinks which are alternately arranged, gold-tin alloy soldering lugs are laid at the upper ends of the semiconductor laser chips and the tungsten copper heat sinks, and aluminum nitride ceramics and zirconium oxide ceramics are alternately arranged at the upper ends of the gold-tin alloy soldering lugs; the number and placement positions of the aluminum nitride ceramics are in one-to-one correspondence with the number and placement positions of the tungsten copper heat sinks, the welding surfaces of the aluminum nitride ceramics are configured to be metal layers, and the non-welding surfaces of the aluminum nitride ceramics are configured to be insulating layers.

Description

Technical Field

[0001] The present disclosure relates to the field of semiconductor laser technology, and more specifically, to a multi-chip laser array welding device and method. Background Art

[0002] Semiconductor laser arrays can achieve a chip center spacing of ≤1mm, and the number of chips can be expanded, so the array is small in size and has a high peak power density. This kind of array packaging is very difficult, mainly because there are a large number of chips (generally ≥3). To reduce the number and time of high-temperature welding of chips, it is hoped that all chips in the array will be sintered into a whole at one time. In this case, the sintering conditions must be set and optimized first to ensure that all chips are successfully welded at one time, and at the same time, it must be ensured that no voids are generated between each chip and the heat sink, because welding voids will cause stress on the chip, affect heat dissipation, and reduce performance and service life. In addition, due to the large number of chips in the array, it is necessary to ensure the consistency of all chip cavity surfaces during welding in order to further control the beam directivity of the entire array. It can be seen that for high-power semiconductor laser arrays, the more chips there are, the more difficult the welding process is. In addition, the soft and hard solders in the traditional welding process are combined, and the soft solder has better ductility, and there is no problem with short-term work, but it is very easy to fatigue and fail under high temperature conditions for a long time, which accelerates the degradation of the chip and reduces the service life of the chip.

[0003] In the process of realizing the concept of the present disclosure, the inventors found that there are at least the following problems in the related technology: multiple high-temperature welding will cause certain damage to the semiconductor laser chip; soft solder is very easy to fatigue when working under high temperature conditions for a long time, which accelerates the degradation of the chip and reduces the service life of the chip; it is very difficult to control the overall neatness of the array and the consistency of the chip cavity surface in the array formed by one-time high-temperature sintering of multiple chips. Summary of the invention

[0004] In view of this, the present disclosure provides a multi-chip laser array welding device and method.

[0005] One aspect of the present disclosure provides a multi-chip laser array welding device, comprising: a base for placing a laser array to be welded; a front end positioning block, arranged at one end of the base, for positioning the laser array to be welded from one end; a rear end positioning block, movably arranged at the other end of the base, for cooperating with the front end positioning block to position the laser array to be welded from the other end; side stop positioning blocks, arranged at both sides of the base, for positioning the laser array to be welded from both sides; an array pressing block, arranged at the upper end of the laser array to be welded, for positioning the laser array to be welded from the upper end; wherein the laser array to be welded comprises alternately arranged semiconductor laser chips and tungsten copper heat sinks, and the welding surfaces of the tungsten copper heat sink and the semiconductor laser chip are provided with a gold-tin solder layer; the upper ends of the semiconductor laser chips and the tungsten copper heat sinks are paved with gold-tin alloy welding sheets, and the upper ends of the gold-tin alloy welding sheets are alternately provided with aluminum nitride ceramics and zirconium oxide ceramics, the number and placement positions of the aluminum nitride ceramics correspond one-to-one to the number and placement positions of the tungsten copper heat sinks, the welding surface of the aluminum nitride ceramics is configured as a metal layer, and the non-welding surface is configured as an insulating layer.

[0006] According to an embodiment of the present disclosure, a side of the base for placing the laser array to be welded is tilted at a preset angle.

[0007] According to an embodiment of the present disclosure, the device also includes: a chip front cavity positioning ceramic, which is arranged on a base; wherein the rear end positioning block is provided with a groove adapted to the chip front cavity positioning ceramic, so that the rear end positioning block can slide along the chip front cavity positioning ceramic.

[0008] According to an embodiment of the present disclosure, the chip front cavity positioning ceramic is configured as an insulator, and its surface is pre-mirror polished.

[0009] According to an embodiment of the present disclosure, an arc-shaped protrusion is provided at one end of the rear end positioning block that contacts the laser array to be welded; wherein the arc-shaped protrusion contacts one side of the tungsten copper heat sink during positioning.

[0010] According to an embodiment of the present disclosure, the device also includes: side positioning ceramics, which are arranged between the side stop positioning block and the laser array to be welded, and are used to maintain the neatness of the laser array to be welded under the positioning action of the side stop positioning block; wherein the surface of the side positioning ceramics is configured as an insulator.

[0011] According to an embodiment of the present disclosure, the device further includes: a rear end slider, which is disposed on the rear end positioning block and can slide together with the rear end positioning block; wherein the rear end slider contacts one side of the aluminum nitride ceramic during positioning.

[0012] According to the embodiments of the present disclosure, the base, the front end positioning block, the rear end positioning block, the side stop positioning block, the array pressing block and the rear end sliding block are all made of tungsten copper material with a low thermal expansion coefficient.

[0013] According to the embodiment of the present disclosure, the thermal expansion coefficient of aluminum nitride ceramic is 5.6×10 -6 / ℃, the thermal expansion coefficient of zirconia ceramics is 10.5×10 -6 / ℃.

[0014] Another aspect of the present disclosure provides a multi-chip laser array welding method, including: obtaining a laser array to be welded; placing the laser array to be welded at a preset position of a multi-chip laser array welding device; using the multi-chip laser array welding device to position the laser array to be welded; welding the laser array to be welded after the positioning process, wherein a gold-tin alloy welding sheet becomes molten at a high temperature and flows toward a metal layer, and automatically disconnects at a position without a metal layer, thereby completing welding between a semiconductor laser chip and a tungsten-copper heat sink, and between a tungsten-copper heat sink and an aluminum nitride ceramic; and removing the zirconium oxide ceramic after condensation to obtain a welded multi-chip laser array.

[0015] Compared with the prior art, the multi-chip laser array welding device and method provided by the present disclosure have at least the following beneficial effects:

[0016] (1) The multi-chip laser array welding device and method provided by the present disclosure forms an assembly by arranging multiple semiconductor laser chips and tungsten copper heat sinks alternately in advance, then laying a whole piece of gold-tin alloy (AuSn) welding sheet on the top of the assembly, and further placing aluminum nitride ceramics and zirconium oxide ceramics alternately on the AuSn welding sheet to form a laser array to be welded, and finally accurately positioning the laser array to be welded, so that multiple semiconductor laser chips and semiconductor laser chips and independent insulating ceramics can be integrated and welded at high temperature once, avoiding damage to the chip caused by multiple high-temperature welding. At the same time, hard solder is used on the welding surface, avoiding the defect of chip degradation caused by fatigue caused by long-term high-temperature operation of soft solder, thereby improving the service life of the chip.

[0017] (2) The multi-chip laser array welding device and method provided by the present disclosure can effectively release the stress caused by all-hard solder welding on the chip through discrete aluminum nitride ceramic welding, further improving the service life of the semiconductor laser.

[0018] (3) The multi-chip laser array welding device and method provided by the present disclosure adopts tungsten-copper material with a low thermal expansion coefficient, which can not only avoid the problem of excessive stress caused by the large thermal expansion coefficient of the material during the welding process, thereby improving the welding quality, but also realize the precise positioning of multiple laser chips, heat sinks and discrete aluminum nitride ceramics, further realizing high-precision integrated welding of multi-chip laser arrays. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] The above and other objects, features and advantages of the present disclosure will become more apparent through the following description of the embodiments of the present disclosure with reference to the accompanying drawings, in which:

[0020] Figure 1 The structure diagram of a multi-chip laser array welding device according to an embodiment of the present disclosure is schematically shown;

[0021] Figure 2 The structure diagram of the laser array to be welded according to the embodiment of the present disclosure is schematically shown;

[0022] Figure 3 The structure of a laser array after welding according to an embodiment of the present disclosure is schematically shown.

[0023] [Reference Signs]

[0024] 1- Base;

[0025] 2-Front end positioning block;

[0026] 3- rear end positioning block;

[0027] 4-Side stop positioning block;

[0028] 5- array block;

[0029] 6-Chip front cavity positioning ceramic;

[0030] 7-side positioning ceramic;

[0031] 8- rear end slider;

[0032] 9-laser array to be welded; 91-semiconductor laser chip; 92-tungsten copper heat sink; 93-AuSn welding sheet; 94-aluminum nitride ceramic; 95-zirconia ceramic;

[0033] 10-The welded laser array. DETAILED DESCRIPTION

[0034] Hereinafter, embodiments of the present disclosure will be described with reference to the accompanying drawings. However, it should be understood that these descriptions are exemplary only and are not intended to limit the scope of the present disclosure. In the following detailed description, for ease of explanation, many specific details are set forth to provide a comprehensive understanding of the embodiments of the present disclosure. However, it is apparent that one or more embodiments may also be implemented without these specific details. In addition, in the following description, descriptions of known structures and technologies are omitted to avoid unnecessary confusion of the concepts of the present disclosure.

[0035] The terms used herein are only for describing specific embodiments and are not intended to limit the present disclosure. The terms "comprise", "include", etc. used herein indicate the existence of the features, steps, operations and / or components, but do not exclude the existence or addition of one or more other features, steps, operations or components.

[0036] All terms (including technical and scientific terms) used herein have the meanings commonly understood by those skilled in the art unless otherwise defined. It should be noted that the terms used herein should be interpreted as having a meaning consistent with the context of this specification and should not be interpreted in an idealized or overly rigid manner.

[0037] When using expressions such as "at least one of A, B, and C, etc.", they should generally be interpreted according to the meaning of the expression commonly understood by those skilled in the art (for example, "a system having at least one of A, B, and C" should include but is not limited to a system having A alone, B alone, C alone, A and B, A and C, B and C, and / or A, B, C, etc.).

[0038] Semiconductor laser arrays can achieve chip center spacing ≤1mm, and the number of chips can be expanded, so the array is small in size and has high peak power density. This kind of array packaging is very difficult, mainly because the number of chips is large (generally ≥3). To reduce the number and time of high-temperature welding of chips, it is hoped that all chips in the array will be sintered into a whole at one time. In this case, the sintering conditions must be set and optimized first to ensure that all chips are successfully welded at one time, and at the same time, it must be ensured that no voids are generated between each chip and the heat sink, because welding voids will cause stress on the chip, affect heat dissipation, and reduce performance and service life. In addition, due to the large number of chips in the array, it is necessary to ensure the consistency of all chip cavity surfaces during welding in order to further control the beam directivity of the entire array. It can be seen that for high-power semiconductor laser arrays, the more chips there are, the more difficult the welding process is. In addition, the soft and hard solders in the traditional welding process are combined, and the soft solder has good ductility and no problem in short-term work, but it is very easy to fatigue and fail under high temperature conditions for a long time, which accelerates the degradation of the chip and reduces the service life of the chip.

[0039] In the process of realizing the concept of the present disclosure, the inventors found that there are at least the following problems in the related technology: multiple high-temperature welding will cause certain damage to the semiconductor laser array; soft solder is very easy to fatigue when working under high temperature conditions for a long time, which will accelerate the degradation of the chip and reduce the service life of the chip; for an array formed by one-time high-temperature sintering of multiple chips, it is very difficult to control the overall neatness of the array and the consistency of the chip cavity surface.

[0040] Based on this, the embodiment of the present disclosure provides a multi-chip laser array welding device to solve the technical problems in the prior art that multiple high-temperature welding is required, which may damage the chip, and the soft solder is prone to fatigue failure, resulting in chip degradation and short service life.

[0041] The device comprises: a base for placing a laser array to be welded; a front end positioning block, arranged at one end of the base, for positioning the laser array to be welded from one end; a rear end positioning block, movably arranged at the other end of the base, for cooperating with the front end positioning block to position the laser array to be welded from the other end; side stop positioning blocks, arranged at both sides of the base, for positioning the laser array to be welded from both sides; an array pressing block, arranged at the upper end of the laser array to be welded, for positioning the laser array to be welded from the upper end; wherein the laser array to be welded comprises alternately arranged semiconductor laser chips and tungsten copper heat sinks, the welding surfaces of the tungsten copper heat sink and the semiconductor laser chip are provided with gold-tin solder layers, the upper ends of the semiconductor laser chips and the tungsten copper heat sinks are paved with gold-tin alloy welding sheets, the upper ends of the gold-tin alloy welding sheets are alternately provided with aluminum nitride ceramics and zirconium oxide ceramics, the number and placement positions of the aluminum nitride ceramics correspond one-to-one to the number and placement positions of the tungsten copper heat sinks, the welding surface of the aluminum nitride ceramics is configured as a metal layer, and the non-welding surface is configured as an insulating layer.

[0042] The multi-chip laser array welding device provided by the embodiment of the present disclosure forms an assembly by arranging multiple semiconductor laser chips and tungsten copper heat sinks alternately in advance, then laying a whole piece of gold-tin alloy (AuSn) welding sheet on the top of the assembly, and further placing aluminum nitride ceramics and zirconium oxide ceramics alternately on the AuSn welding sheet to form a laser array to be welded, and finally accurately positioning the laser array to be welded, so that multiple semiconductor laser chips and semiconductor laser chips and independent insulating ceramics can be integrated and welded at high temperature once, avoiding damage to the chip caused by multiple high-temperature welding. At the same time, hard solder is used on the welding surface, avoiding the defect of chip degradation caused by fatigue caused by long-term high-temperature operation of soft solder, and improving the service life of the chip.

[0043] In order to make the objectives, technical solutions and advantages of the present disclosure more clearly understood, the present disclosure is further described in detail below in conjunction with specific embodiments and with reference to the accompanying drawings.

[0044] Figure 1 The structure diagram of a multi-chip laser array welding device according to an embodiment of the present disclosure is schematically shown.

[0045] like Figure 1 As shown, the multi-chip laser array welding device of this embodiment may include: a base 1, a front end positioning block 2, a rear end positioning block 3, a side stop positioning block 4 and an array pressing block 5.

[0046] The base 1 is used to place the laser array 9 to be welded.

[0047] In this embodiment, the laser array 9 to be welded includes semiconductor laser chips 91 and tungsten copper heat sinks 92 that are alternately arranged, wherein a gold-tin solder layer is preset on the welding surface of the tungsten copper heat sink 92 and the semiconductor laser chip 91 .

[0048] A whole AuSn solder sheet 93 is laid on the upper end of the semiconductor laser chip 91 and the tungsten copper heat sink 92. Aluminum nitride ceramics 94 and zirconium oxide ceramics 95 are alternately arranged on the upper end of the AuSn solder sheet 93. The number and placement positions of the aluminum nitride ceramics 94 correspond to the number and placement positions of the tungsten copper heat sink 92 (the zirconium oxide ceramics 95 are arranged between the aluminum nitride ceramics 94 to position the aluminum nitride ceramics 94 and ensure that the positions of the aluminum nitride ceramics 94 and the tungsten copper heat sink 92 correspond).

[0049] The welded surface of the aluminum nitride ceramic 94 is configured as a metal layer, and the non-welded surface is configured as an insulating layer. In addition, all surfaces of the zirconium oxide ceramic 95 are configured as insulating layers.

[0050] In this embodiment, the base 1 can be designed with an angle of inclination, that is, one side of the base 1 for placing the laser array 9 to be welded is inclined at a preset angle, so that the parts placed thereon can obtain the fixing force generated by the gravity component.

[0051] The front end positioning block 2 is disposed at one end of the base 1 and is used to position the laser array 9 to be welded from one end.

[0052] In this embodiment, the front end positioning block 2 has a groove, and can be fixed to the front end of the base 1 by screws, for example, to position the laser array 9 to be welded from the front end.

[0053] The rear end positioning block 3 is movably disposed at the other end of the base 1, and is used to cooperate with the front end positioning block 2 to position the laser array 9 to be welded from the other end.

[0054] In this embodiment, the rear end positioning block 3 can be movably arranged at the rear end of the base 1, and can slide in the direction of the front end positioning block 2, so as to facilitate the front and rear bidirectional positioning with the front end positioning block 2. In addition, an arc-shaped protrusion is provided at one end of the rear end positioning block 3 that contacts the laser array 9 to be welded, so as to prevent the semiconductor laser chip 91 and the tungsten copper heat sink 92 from being tilted due to severe force. The arc-shaped protrusion contacts one side of the tungsten copper heat sink 92 in the laser array 9 to be welded during positioning.

[0055] The side stop positioning blocks 4 are arranged on both sides of the base 1 for positioning the laser array 9 to be welded from both sides.

[0056] In this embodiment, the side stop positioning blocks 4 are respectively fixedly disposed on the left and right sides of the base 1 for positioning on the left and right sides.

[0057] The array pressing block 5 is arranged at the upper end of the laser array to be welded, and is used to position the laser array to be welded from the upper end.

[0058] In this embodiment, after the laser array 9 to be welded is placed, the array pressing block 5 applies pressure from the top to ensure that the tungsten copper heat sink 92 and the aluminum nitride ceramic 94 are well welded.

[0059] It can be seen that in this embodiment, the front end positioning block 2, the rear end positioning block 3, the side stop positioning block 4 and the array pressing block 5 respectively perform all-round positioning of the laser array 9 to be welded in the front and back, left and right, and up and down directions. The zirconia ceramic 95 plays a role of discrete interval positioning of the aluminum nitride ceramic 94, so that the laser array 9 to be welded can achieve precise integrated welding during the welding process.

[0060] The multi-chip laser array welding device provided by the embodiment of the present disclosure forms an assembly by arranging multiple semiconductor laser chips 91 and tungsten copper heat sinks 92 alternately in advance, and then laying a whole piece of AuSn welding sheet 93 on the top of the assembly, and further alternately placing aluminum nitride ceramics 94 and zirconium oxide ceramics 95 on the AuSn welding sheet 93 to form a laser array 9 to be welded, and finally accurately positioning the laser array 9 to be welded, so that multiple semiconductor laser chips 91 and semiconductor laser chips 91 and independent insulating ceramics (aluminum nitride ceramics 94) can be integrated and welded through one high temperature, avoiding damage to the chip caused by multiple high-temperature welding. At the same time, hard solder is used on the welding surface, avoiding the defect of chip degradation caused by fatigue of soft solder due to long-term high-temperature operation, thereby improving the service life of the chip.

[0061] According to an embodiment of the present disclosure, the multi-chip laser array welding device may further include: a chip front cavity positioning ceramic 6 , a side positioning ceramic 7 and a rear end slider 8 .

[0062] The chip front cavity positioning ceramic 6 is fixed on the base 1. The rear end positioning block 3 is provided with a groove adapted to the chip front cavity positioning ceramic 6, and the two form a slide rail structure, so that the rear end positioning block 3 can slide along the chip front cavity positioning ceramic 6.

[0063] In this embodiment, the chip front cavity positioning ceramic 6 has no metal layer and is an insulating member, and its surface is mirror-polished to prevent the chip front cavity from being scratched.

[0064] The side positioning ceramic 7 is arranged between the side stop positioning block 4 and the laser array 9 to be welded, and is used to maintain the neatness of the laser array 9 to be welded under the positioning effect of the side stop positioning block 4.

[0065] In this embodiment, the side positioning ceramic 7 is arranged on both sides of the laser array 9 to be welded, and the side stop positioning block 4 can position the laser array 9 to be welded from both sides through the side positioning ceramic 7. The side positioning ceramic 7 has no metal layer on its surface and is an insulating member, and its height is in the middle position of the aluminum nitride ceramic 13 in the unwelded laser array 9.

[0066] The rear end slider 8 is arranged on the rear end positioning block 3 and can slide with the rear end positioning block 3 to play the role of rear end positioning. The rear end slider 8 contacts one side of the aluminum nitride ceramic in the laser array 9 to be welded during positioning.

[0067] According to the embodiments of the present disclosure, the base 1, the front end positioning block 2, the rear end positioning block 3, the side stop positioning block 4, the array pressure block 5 and the rear end slider 8 are all made of tungsten copper material with a low thermal expansion coefficient to prevent high temperature welding from affecting the laser array welding accuracy and welding quality.

[0068] The multi-chip laser array welding device provided in the embodiment of the present disclosure adopts tungsten-copper material with a low thermal expansion coefficient, which not only avoids the problem of excessive stress caused by the large thermal expansion coefficient of the material during welding, thereby improving the welding quality, but also realizes the precise positioning of multiple laser chips, heat sinks and discrete aluminum nitride ceramics, further realizing high-precision integrated welding of multi-chip laser arrays.

[0069] In this embodiment, the aluminum nitride ceramics 94 and the zirconium oxide ceramics 95 on the AuSn welding sheet 93 are arranged alternately, that is, the aluminum nitride ceramics 94 can be separately arranged first, and then the zirconium oxide ceramics 95 can be arranged between the aluminum nitride ceramics 94 to fill the vacancies and position the aluminum nitride ceramics 94, so that each aluminum nitride ceramic 94 is precisely located above each tungsten copper heat sink 92, and the surface of the zirconium oxide ceramic 95 has no metal layer and is an insulating part.

[0070] The thermal expansion coefficient of aluminum nitride ceramic 94 is 5.6×10 -6 / ℃, the thermal expansion coefficient of zirconia ceramic 95 is 10.5×10 -6 / ℃, in comparison, the thermal expansion coefficient of the zirconia ceramic 95 is significantly greater than that of the aluminum nitride ceramic 94, so after high-temperature welding condensation, the gaps between the aluminum nitride ceramics 94 become larger, and the zirconia ceramic 95 can be smoothly taken out.

[0071] The multi-chip laser array welding device provided in the embodiment of the present disclosure can effectively release the stress caused to the chip by all-hard solder welding through discrete aluminum nitride ceramic welding, thereby further improving the service life of the semiconductor laser.

[0072] Based on the chip laser array welding device of the embodiment of the present disclosure, the embodiment of the present disclosure also provides a multi-chip laser array welding method, which may include operations S1 to S5, for example.

[0073] In operation S1 , a laser array 9 to be welded is obtained.

[0074] In operation S2, the laser array 9 to be welded is placed at a preset position of the multi-chip laser array welding device.

[0075] In operation S3 , the laser array 9 to be welded is positioned using a multi-chip laser array welding device.

[0076] In operation S4, the laser array to be welded after the positioning process is welded, wherein the gold-tin alloy welding sheet becomes molten at high temperature and flows toward the metal layer, and automatically disconnects at the position without the metal layer, thereby completing the welding between the semiconductor laser chip and the tungsten-copper heat sink, and the tungsten-copper heat sink and the aluminum nitride ceramic.

[0077] In operation S5, the zirconium oxide ceramic is removed after condensation to obtain a welded multi-chip laser array.

[0078] In order to achieve the best welding effect, the laser array 9 to be welded can be obtained, for example, in the following manner.

[0079] In this embodiment, for example, the laser array 9 to be welded can be obtained by using three semiconductor laser chips 91 and four tungsten copper heat sinks 92. Specifically:

[0080] Starting from the position of the front end positioning block 2, the tungsten copper heat sink 92 is placed first, and then the semiconductor laser chip 91 is placed, and the two are placed alternately in sequence.

[0081] The first tungsten copper heat sink 92 is welded to the P surface of the semiconductor laser chip 91, which is equivalent to the positive electrode. One side of the second and third tungsten copper heat sinks 92 is welded to the N surface of the semiconductor laser chip 91. The other side of the second and third tungsten copper heat sinks 92 is welded to the P surface of the semiconductor laser chip 91, which is equivalent to connecting the positive and negative electrodes of the chip in series. The fourth tungsten copper heat sink 92 is welded to the N surface of the semiconductor laser chip 91 to form the negative electrode of the array. The welding surface of the tungsten copper heat sink 92 can be pre-set with a solder layer, or a solder sheet can be used.

[0082] The length of the tungsten copper heat sink 92 is consistent with the length of the semiconductor laser chip 91, and the height is slightly higher than the semiconductor laser chip 91 to prevent the molten solder from adhering to the back cavity surface of the semiconductor laser chip 91 during high-temperature welding, causing a short circuit between the P and N surfaces.

[0083] The front cavity of the semiconductor laser chip 91 and one side of the tungsten copper heat sink 92 are placed on the chip front cavity positioning ceramic 6. The chip front cavity positioning ceramic 6 is mirror polished, which can not only ensure the uniformity of the laser array light-emitting surface, but also avoid scratches on the front cavity of the semiconductor laser chip 91.

[0084] The semiconductor laser chip 91 and the tungsten copper heat sink 92 are positioned left and right by the side positioning ceramics 7 on both sides, and the rear end positioning block 3 is used to make the plurality of semiconductor laser chips 91 and the tungsten copper heat sink 92 closely contact and position them.

[0085] A whole piece of AuSn solder sheet 93 is placed on the semiconductor laser chip 91 and the tungsten copper heat sink 92. The size of the AuSn solder sheet 93 is consistent with the size of the semiconductor laser chip 91 and the tungsten copper heat sink 92 after they are combined. Compared with using a separate solder sheet to position the welding surface of each tungsten copper heat sink 92 and aluminum nitride ceramic 94, this method cannot be accurately positioned due to too many scattered parts in the array. Therefore, using a whole piece of AuSn solder sheet 93 is more suitable for multi-chip array welding.

[0086] Aluminum nitride ceramics 94 and zirconium oxide ceramics 95 are placed alternately on the AuSn solder sheet 93, that is, they are placed in an interval order. The number and placement of aluminum nitride ceramics 94 correspond to the number and placement of tungsten copper heat sinks 92. Zirconia ceramics 95 do not have a metal layer pre-set on the surface and are insulating parts. The welding surface of aluminum nitride ceramics 94 is pre-set with a metal layer, and the non-welding surface remains in an insulating state. Among them, the height of zirconium oxide ceramics 95 is slightly lower than that of aluminum nitride ceramics 94. Discrete aluminum nitride ceramics 94 can effectively release the stress caused to the chip by all-hard solder welding.

[0087] At this point, the semiconductor laser chip 91, the tungsten copper heat sink 92, the AuSn welding sheet 93 and the aluminum nitride ceramic 94 and the zirconium oxide ceramic 95 at the corresponding positions constitute the laser array 9 to be welded. The structure of the laser array 9 to be welded is shown in FIG. Figure 2 shown.

[0088] Figure 2 The structure of a laser array to be welded according to an embodiment of the present disclosure is schematically shown.

[0089] like Figure 2 As shown, the laser array 9 to be welded in this embodiment includes: a semiconductor laser chip 91 , a tungsten-copper heat sink 92 , an AuSn welding sheet 93 , an aluminum nitride ceramic 94 and a zirconium oxide ceramic 95 .

[0090] An array pressing block 5 is placed on the laser array 9 to be welded. Since the height of the zirconia ceramic 95 is slightly lower than the aluminum nitride ceramic 94, the pressure of the array pressing block 5 will be applied entirely on the aluminum nitride ceramic 94, which can ensure the welding quality of the tungsten copper heat sink 92 and the aluminum nitride ceramic 94. A rear slider 8 is placed at the rear end of the laser array 9 to be welded to fix multiple aluminum nitride ceramics 94 and zirconia ceramics 95.

[0091] During high-temperature welding, a whole piece of AuSn solder sheet 93 will flow toward the metal layer when in a molten state at high temperature, and the position without the metal layer will be automatically disconnected, completing the welding of the aluminum nitride ceramic 94 and the tungsten copper heat sink 92. Finally, the welding between the semiconductor laser chip 91 and the tungsten copper heat sink 92, and the tungsten copper heat sink 92 and the aluminum nitride ceramic 94 is achieved.

[0092] The thermal expansion coefficient of aluminum nitride ceramic 94 is 5.6×10 -6 / ℃, the thermal expansion coefficient of zirconia ceramic 95 is 10.5×10 -6 / ℃, in comparison, the thermal expansion coefficient of the zirconia ceramic 95 is significantly greater than that of the aluminum nitride ceramic 94, so after high-temperature welding condensation, the gaps between the aluminum nitride ceramics 94 become larger, and the zirconia ceramic 95 can be smoothly taken out, eventually forming a welded laser array 10. The structure of the welded laser array 10 is shown in Figure 3.

[0093] Figure 3 The structure of a laser array after welding according to an embodiment of the present disclosure is schematically shown.

[0094] like Figure 3 As shown, the welded laser array 10 of this embodiment includes: a semiconductor laser chip 91 , a tungsten copper heat sink 92 and an aluminum nitride ceramic 94 .

[0095] It should be understood that the multi-chip laser array welding method provided in the embodiment of the present disclosure is applicable to welding of other hard solders as well as welding of other semiconductor laser chips.

[0096] The flowcharts and block diagrams in the accompanying drawings illustrate the possible implementation architecture, functions and operations of the systems, methods and computer program products according to various embodiments of the present disclosure. In this regard, each box in the flowchart or block diagram may represent a module, a program segment, or a part of a code, and the above-mentioned module, program segment, or a part of the code contains one or more executable instructions for implementing the specified logical function. It should also be noted that in some alternative implementations, the functions marked in the box may also occur in an order different from that marked in the accompanying drawings. For example, two boxes represented in succession can actually be executed substantially in parallel, and they can sometimes be executed in the opposite order, depending on the functions involved. It should also be noted that each box in the block diagram or flowchart, and the combination of boxes in the block diagram or flowchart, can be implemented with a dedicated hardware-based system that performs a specified function or operation, or can be implemented with a combination of dedicated hardware and computer instructions. It can be understood by those skilled in the art that the features recorded in the various embodiments of the present disclosure can be combined and / or combined in a variety of ways, even if such a combination or combination is not explicitly recorded in the present disclosure. In particular, without departing from the spirit and teaching of the present disclosure, the features described in the various embodiments of the present disclosure may be combined and / or combined in a variety of ways. All of these combinations and / or combinations fall within the scope of the present disclosure.

[0097] The embodiments of the present disclosure are described above. However, these embodiments are only for illustrative purposes and are not intended to limit the scope of the present disclosure. Although the embodiments are described above, this does not mean that the measures in the various embodiments cannot be used in combination to advantage. Without departing from the scope of the present disclosure, those skilled in the art may make a variety of substitutions and modifications, which should all fall within the scope of the present disclosure.

Claims

1. A multi-chip laser array welding device, characterized in that: The device comprises: A base, used for placing the laser array to be welded; A front end positioning block is provided at one end of the base and is used to position the laser array to be welded from one end; A rear end positioning block is movably arranged at the other end of the base, and is used to cooperate with the front end positioning block to position the laser array to be welded from the other end; Side stop positioning blocks are provided on both sides of the base and are used to position the laser array to be welded from both sides; An array pressing block is arranged at the upper end of the laser array to be welded, and is used to position the laser array to be welded from the upper end; Wherein, the laser array to be welded comprises semiconductor laser chips and tungsten copper heat sinks arranged alternately, and the welding surfaces of the tungsten copper heat sink and the semiconductor laser chip are provided with a gold-tin solder layer; The upper ends of the semiconductor laser chip and the tungsten-copper heat sink are paved with gold-tin alloy solder sheets, and the upper ends of the gold-tin alloy solder sheets are alternately provided with aluminum nitride ceramics and zirconium oxide ceramics, the number and placement positions of the aluminum nitride ceramics correspond one-to-one to the number and placement positions of the tungsten-copper heat sinks, the welding surface of the aluminum nitride ceramic is configured as a metal layer, and the non-welding surface is configured as an insulating layer.

2. The device according to claim 1, characterized in that The base is used to place a surface of the laser array to be welded, and is tilted at a preset angle.

3. The device according to claim 2, characterized in that The device also includes: A chip front cavity positioning ceramic is arranged on the base; The rear end positioning block is provided with a groove matched with the chip front cavity positioning ceramic, so that the rear end positioning block can slide along the chip front cavity positioning ceramic.

4. The device according to claim 2, characterized in that The chip front cavity positioning ceramic is configured as an insulator, and its surface is pre-mirror polished.

5. The device according to claim 3, characterized in that An arc-shaped protrusion is provided at one end of the rear end positioning block that contacts the laser array to be welded; Wherein, the arc-shaped protrusion contacts one side of the tungsten copper heat sink during positioning.

6. The device according to claim 2, characterized in that The device also includes: Side positioning ceramics, arranged between the side stop positioning block and the laser array to be welded, and used for maintaining the neatness of the laser array to be welded under the positioning effect of the side stop positioning block; Wherein, the surface of the side positioning ceramic is configured as an insulator.

7. The device according to claim 2, characterized in that The device also includes: A rear end sliding block is provided on the rear end positioning block and can slide along with the rear end positioning block; Wherein, the rear end slider contacts one side of the aluminum nitride ceramic during positioning.

8. The device according to claim 2, characterized in that The base, the front end positioning block, the rear end positioning block, the side stop positioning block, the array pressing block and the rear end sliding block are all made of tungsten copper material with a low thermal expansion coefficient.

9. The device according to claim 2, characterized in that The thermal expansion coefficient of the aluminum nitride ceramic is 5.6×10 -6 / ℃, the thermal expansion coefficient of the zirconia ceramic is 10.5×10 -6 / ℃.

10. A multi-chip laser array welding method, characterized in that: The method comprises: Obtaining a laser array to be welded; Placing the laser array to be welded at a preset position of a multi-chip laser array welding device, wherein the multi-chip laser array welding device is the multi-chip laser array welding device according to any one of claims 1 to 9; Using the multi-chip laser array welding device to perform positioning processing on the laser array to be welded; The laser array to be welded after the positioning process is welded, wherein the gold-tin alloy welding sheet becomes molten at high temperature and flows to the metal layer, and automatically disconnects at the position without the metal layer, thereby completing the welding between the semiconductor laser chip and the tungsten-copper heat sink, and between the tungsten-copper heat sink and the aluminum nitride ceramic; After condensation, the zirconia ceramic is removed to obtain a welded multi-chip laser array.

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