A high-efficiency semiconductor laser packaging auxiliary device and a packaging method

Abstract

The application relates to the technical field of semiconductor laser packaging, in particular to a high-efficiency semiconductor laser packaging auxiliary device and a packaging method. The packaging auxiliary device comprises a cooler, a secondary heat sink, an integrated L-shaped electrode, a first insulating sheet and a second insulating sheet. The upper surface of the cooler is provided with a first groove for accommodating the secondary heat sink; the upper surface of the secondary heat sink is provided with a second groove, the second groove is provided with a plurality of third grooves which are arranged at intervals and parallel to each other, the bottom surface of the second groove between the adjacent third grooves is provided with a boss, and the two ends of the secondary heat sink are provided with openings which are arranged parallel to the second groove. The integrated L-shaped electrode is arranged on the cooler. The technical scheme of the application can effectively reduce the packaging difficulty of the semiconductor laser, improve the packaging efficiency and reduce the packaging cost.

Description

Technical Field

[0001] This invention relates to the field of semiconductor laser packaging technology, and more specifically to a high-efficiency packaging auxiliary device and packaging method for semiconductor lasers. Background Technology

[0002] The information disclosed in the background section of this invention is intended only to enhance the understanding of the overall background of the invention and is not necessarily to be construed as an admission or in any way implying that such information constitutes prior art known to those skilled in the art.

[0003] Macrochannel semiconductor lasers, due to their small size, high efficiency, and stable performance, are widely used in the medical aesthetics market and have become the core light source for mainstream hair removal devices. Currently, the conventional packaging solution for these products involves spreading solder above the heat dissipation channel, placing an aluminum nitride ceramic sheet, spreading solder on top of the ceramic sheet, and then placing a heat sink so that the laser chip is directly beneath the non-metallic area of ​​the aluminum nitride ceramic sheet for insulation. During the placement of the heat sink, 10mm long strips must be placed parallel to each other in the insulating groove under a stereomicroscope. Because the aluminum nitride ceramic sheet is not fixed in place, it may shift, requiring frequent adjustments to the positions of various components to achieve proper alignment, which is very time-consuming and labor-intensive.

[0004] Furthermore, the typical electrical structure of semiconductor lasers on the market involves soldering two L-shaped electrodes to two separate printed circuit boards (PCBs), and then soldering the two L-shaped electrodes together. This process is prone to uneven soldering and heat buildup over time, which can lead to open circuits in the module. In addition, electrode pads are usually placed between the L-shaped electrode pad at the top of the module and the heat sinks at the top and bottom edges to achieve electrical connection between the sensor and the L-shaped electrode pad. For aesthetic purposes, the L-shaped electrode pad, after adding the electrode pads, is the same height as the edge heat sinks. This bonding area is small, and poor solder adhesion or misalignment can cause the electrode pads to detach and the module to open. Summary of the Invention

[0005] This invention provides an efficient packaging auxiliary device and packaging method for semiconductor lasers, which can effectively reduce the packaging difficulty of semiconductor lasers, improve packaging efficiency, and reduce packaging costs. Specifically, this invention discloses the following technical solutions.

[0006] In a first aspect, this invention discloses an efficient packaging auxiliary device for semiconductor lasers, comprising: a cooler, a secondary heat sink, an integrated L-shaped electrode, a first insulating sheet, and a second insulating sheet. The cooler has a first groove on its upper surface for accommodating the secondary heat sink, and a second groove on its upper surface. The second groove contains several spaced-apart and parallel third grooves. A boss is located on the bottom surface of the second groove between adjacent third grooves, and both ends of the secondary heat sink have openings parallel to the second grooves. The integrated L-shaped electrode comprises an L-shaped plate, a horizontal plate, and a vertical plate. The L-shaped plate is vertically positioned and adheres to the outer wall of the cooler, with the first insulating sheet is used to insulate the two surfaces. The horizontal plate is horizontally connected to the top of the L-shaped plate, and is positioned on the upper surface of the cooler without contacting it. The end of the horizontal plate, after passing through the opening, is located in the adjacent second groove, allowing the integrated L-shaped electrode to energize the bar array therein. The vertical plate is vertically connected to the lower end of the "L"-shaped plate. The vertical plate is used to cover the outer side wall of the cooler and the two are isolated and insulated by the second insulating sheet. The first insulating sheet and the second insulating sheet are located on two adjacent side walls.

[0007] Furthermore, the cooler has an inner cavity and its bottom surface has an inlet and an outlet communicating with the inner cavity.

[0008] Furthermore, the cooler includes a base and a cover plate. The base has an inner cavity and an opening on its upper surface, with the liquid inlet and outlet located on the bottom surface of the base. The cover plate seals over the opening on the upper surface of the base, and its lower surface has several heat dissipation columns located within the inner cavity of the base.

[0009] Furthermore, the end of the cross plate is supported on the upper surface of the secondary heat sink in the opening, thereby creating a gap between the cross plate and the cooler to insulate them.

[0010] Furthermore, the two outer side walls and the top surface of the boss have a conductive layer. Optionally, the conductive layer is made of any one of gold, copper, etc.

[0011] Preferably, the secondary heat sink is a boron nitride insulating sheet.

[0012] Secondly, the present invention discloses a high-efficiency packaging method for semiconductor lasers, comprising the following steps:

[0013] (1) A number of bar strips and strip-shaped primary heat sinks are arranged in an alternating manner and then sintered into a bar strip array, wherein the bottom of the connecting surface between adjacent primary heat sinks has a fourth groove that matches the boss.

[0014] (2) The bar array is embedded and fixed in the second groove of the secondary heat sink of the packaging auxiliary equipment, and the boss is located in the fourth groove, and adhesive is filled between the two. Each of the third grooves corresponds to a bar.

[0015] (3) The integrated L-shaped electrode, the first insulating sheet, and the second insulating sheet are assembled and connected to their corresponding positions as described above and fixed with clamps. The end of the horizontal plate is then connected to the outermost primary heat sink of the bar array. An electrode structure consisting of the integrated L-shaped electrode, the first insulating sheet, and the second insulating sheet is provided on each side of the bar array. Solder is applied between the integrated L-shaped electrode, the cooler, and the first and second insulating sheets. Finally, sintering is performed to obtain the packaged semiconductor laser.

[0016] Furthermore, in step (1), a groove is provided at a lower corner of the primary heat sink along its length, and the grooves of adjacent primary heat sinks form the fourth groove. By providing the fourth groove and its corresponding boss, the time spent by the operator aligning the bar strip and the third groove under a microscope can be significantly reduced.

[0017] Furthermore, in step (2), the height of the bar array is greater than the depth of the second groove.

[0018] Compared with the prior art, the technical solution provided by the present invention has at least the following beneficial effects:

[0019] 1. The packaging auxiliary device of the present invention enables rapid positioning and connection of the secondary heat sink and the cooler through a first groove on the cooler. This eliminates the problem of displacement of the secondary heat sink caused by placing adhesive or bar strips on it, which necessitates repeated adjustments to the positions of various components to ensure proper alignment. This improves the packaging efficiency of the semiconductor laser. Simultaneously, the first groove also reduces the distance between the secondary heat sink and the coolant in the cooler, which is beneficial for heat dissipation during laser operation.

[0020] 2. This invention not only provides a second groove on the secondary heat sink, enabling rapid positioning and assembly of the bar array, but also, through a boss on the bottom surface of the second groove and a stepped design with grooves on the primary heat sink, the bottom of the connecting surface between adjacent primary heat sinks in the formed bar array has a fourth groove matching the boss. Thus, when assembling the bar array into the second groove, the boss allows for quick alignment of the bar with the third groove in the second groove. Furthermore, the space left between the boss and the fourth groove can be filled with adhesive, improving the connection strength between the bar array and the secondary heat sink. Simultaneously, the above connection method effectively increases the conductive area between the bar and the secondary heat sink, reduces resistance, and improves the reliability of laser operation.

[0021] 3. This invention uses a specially constructed integrated L-shaped electrode to replace the scattered components such as L-shaped electrode sheet A, L-shaped electrode sheet B, and electrode sheets at both ends of the bar array used in traditional semiconductor laser packaging. The openings at both ends of the secondary heat sink significantly increase the contact area between the integrated L-shaped electrode and the bar array, effectively avoiding electrical connection problems such as poor adhesion and increased resistance at the electrode sheets at both ends of the bar array, which are common in traditional packaging processes. This improves the reliability of the laser during long-term operation. Attached Figure Description

[0022] The accompanying drawings, which form part of this invention, are used to provide a further understanding of the invention. The illustrative embodiments of the invention and their descriptions are used to explain the invention and do not constitute an improper limitation of the invention.

[0023] Figure 1 The following is a schematic diagram of the structure of the cooler in the embodiments below.

[0024] Figure 2 The following is a schematic diagram of the structure of the secondary heat sink in the embodiments below.

[0025] Figure 3 The following is a schematic diagram of the structure after the auxiliary equipment and bar array are assembled in the embodiments.

[0026] Figure 4 The following is a cross-sectional view of the assembly of the auxiliary equipment and bar array in the embodiment.

[0027] Figure 5 The following is a partially enlarged cross-sectional view of the assembly of the auxiliary equipment and bar array in the embodiments.

[0028] Figure 6 The following is a schematic diagram of the cover plate in the embodiments.

[0029] Figure 7 The following is a schematic diagram of the structure of another cooler in the embodiments below.

[0030] The reference numerals in the diagram represent: 1-cooler, 2-secondary heat sink, 3-integrated L-shaped electrode, 4-first insulating sheet, 5-second insulating sheet, 6-bar, 7-primary heat sink, 101-first groove, 102-liquid inlet, 103-liquid outlet, 104-base, 105-cover plate, 106-heat dissipation column, 201-second groove, 202-third groove, 203-protrusion, 204-opening, 205-fourth groove, 301-"L" shaped plate, 302-horizontal plate, 303-vertical plate. Detailed Implementation

[0031] It should be noted that the following detailed description is illustrative and intended to provide further explanation of the invention. Unless otherwise specified, all technical and scientific terms used in this invention have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains.

[0032] For ease of description, the terms "up," "down," "left," and "right" appearing in this invention only indicate that they correspond to the up, down, left, and right directions in the accompanying drawings. They do not limit the structure and are merely used to facilitate the description of the invention and to simplify the description. They do not indicate or imply that the device or component referred to needs to have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of the invention. Furthermore, any methods and materials similar to or equivalent to those described can be applied to the methods of this invention.

[0033] refer to Figure 1 , Figure 2 and Figure 3 Example: A high-efficiency packaging auxiliary device for semiconductor lasers includes: a cooler 1, a secondary heat sink 2, an integrated L-shaped electrode 3, a first insulating sheet 4, and a second insulating sheet 5.

[0034] The cooler 1 is a cubic structure with cooling function to remove the heat generated by the semiconductor laser structure fixed on its upper surface during operation. The upper surface of the cooler 1 has a rectangular first groove 101 for accommodating the secondary heat sink 2, and the first groove 101 is used to embed and fix the bar array. The first groove 101 allows the secondary heat sink 2 to be quickly positioned and connected to the cooler 1, saving the problems of traditional packaging methods where adhesive is needed on the secondary heat sink 2, and the placement of the bar array can easily cause displacement of the secondary heat sink 2, leading to the need for repeated adjustments to the positions of various components to achieve proper alignment. This improves the packaging efficiency of the semiconductor laser. Simultaneously, the first groove 101 also reduces the distance between the secondary heat sink 2 and the coolant in the cooler 1, which is beneficial for heat dissipation during laser operation.

[0035] refer to Figure 2 The upper surface of the secondary heat sink 2 has a rectangular second groove 201. This second groove 201 contains several spaced-apart and parallel third grooves 202. A boss 203 is located at the midpoint of the bottom surface of the second groove 201 between adjacent third grooves 202. The boss 203 is integrally connected to the bottom surface of the second groove 201. The two outer side walls and the top surface of the boss 203 have a conductive layer. The conductive layer can be made of materials such as gold or copper.

[0036] Furthermore, each end of the secondary heat sink 2 has an opening 204, and the opening 204 is arranged parallel to the second groove 201. In this embodiment, the second groove 201 can quickly complete the positioning and assembly of the bar array on the secondary heat sink 2. Moreover, by providing a boss 203 on the bottom surface of the second groove 201 and providing the primary heat sink 7 with a stepped shape having grooves, the bottom of the connecting surface between adjacent primary heat sinks 7 in the formed bar array has a fourth groove 205 that matches the boss 203. In this way, when assembling the bar array into the second groove 201, the boss 203 can quickly align the bar 6 with the third groove 202 in the second groove 201, which can shorten the assembly time by more than 5 minutes per unit compared to the traditional method. At the same time, the above connection method effectively increases the conductive area between the bar and the secondary heat sink 2, reduces the resistance, and improves the reliability of laser operation.

[0037] refer to Figure 3 The integrated L-shaped electrode 3 includes an L-shaped plate 301, a horizontal plate 302, and a vertical plate 303. The L-shaped plate 301 is vertically positioned and is attached to the outer side wall of the cooler 1, with the two insulated by the first insulating sheet 4. The horizontal plate 302 is horizontally connected to the top of the L-shaped plate 301 and is positioned on the upper surface of the cooler 1. In use, the end of the horizontal plate 302 supports the upper surface of the secondary heat sink 2 in the opening 204, thus creating a gap between the horizontal plate 302 and the cooler 1 for insulation. Simultaneously, the end of the horizontal plate 302 passes through the opening 204 and is located in the adjacent second groove 201, allowing the integrated L-shaped electrode 3 to energize the bar array therein.

[0038] Furthermore, the vertical plate 303 is vertically connected to the lower end of the "L"-shaped plate 301. The vertical plate 303 is used to cover the outer wall of the cooler 1, and the two are isolated and insulated by the second insulating sheet 5. The first insulating sheet 4 and the second insulating sheet 5 are located on two adjacent side walls. The integrated L-shaped electrode 3 can be formed by gold plating on a brass surface. In this embodiment, a specially constructed integrated L-shaped electrode 3 is used to replace the scattered components such as L-shaped electrode sheet A, L-shaped electrode sheet B, and electrode sheets at both ends of the bar array used in traditional semiconductor laser packaging. The openings 204 at both ends of the secondary heat sink 2 can significantly increase the contact area between the integrated L-shaped electrode 3 and the bar array, which can effectively avoid the problems of poor adhesion and increased resistance at the electrode sheets at both ends of the bar array in traditional packaging processes, thus improving the reliability of the laser in long-term operation.

[0039] In a more specific embodiment, the cooler 1 of the high-efficiency packaging auxiliary equipment for semiconductor lasers described in the above embodiments has an inner cavity and an inlet 102 and an outlet 103 communicating with the inner cavity on its bottom surface. Coolant (such as water) enters the inner cavity of the cooler 1 from the inlet 102 and then exits from the outlet 103 to remove the heat generated during laser operation and ensure the normal operation of the laser.

[0040] In a preferred embodiment, the cooler 1 of the high-efficiency packaging auxiliary device for semiconductor lasers described in the above embodiments includes a base 104 and a cover plate 105. (See reference...) Figure 6 and Figure 7 The base 104 has an inner cavity and an open upper surface. The liquid inlet 102 and the liquid outlet 103 are located on the bottom surface of the base 104. The cover plate 105 covers the opening on the upper surface of the base 104 to form a seal, and the lower surface of the cover plate 105 has a plurality of heat dissipation columns 106 located in the inner cavity of the base 104. The heat dissipation columns 106 help to increase the heat conduction area and accelerate heat dissipation.

[0041] In a preferred embodiment, the secondary heat sink 2 of the high-efficiency packaging auxiliary equipment for semiconductor lasers described in the above embodiments is a boron nitride insulating sheet. Compared with the traditional aluminum nitride secondary heat sink, boron nitride has a thermal conductivity of over 2000 W / mK and excellent high-temperature resistance. Furthermore, boron nitride has a smaller coefficient of thermal expansion than aluminum nitride, enabling the fabrication of bar arrays to achieve higher thermal conductivity without introducing greater thermal stress.

[0042] In another embodiment, using the semiconductor laser high-efficiency packaging auxiliary equipment described in the above embodiments as an example, a semiconductor laser packaging method is provided, specifically including the following steps:

[0043] (1) A plurality of bar strips 6 and strip-shaped primary heat sinks 7 are arranged in an alternating pattern and then sintered together to form a bar strip array. Wherein: a lower corner of each primary heat sink 7 has a groove arranged along its length, and the grooves of adjacent primary heat sinks 7 form a fourth groove 205, thereby forming a fourth groove 205 matching the boss 203 at the bottom of the connecting surface between adjacent primary heat sinks 7. By setting the fourth groove 205 and its corresponding boss 203, the time required for the operator to align the bar strips 6 and the third groove 202 under a microscope can be significantly reduced.

[0044] (2) The bar array is embedded and fixed in the second groove 201 of the secondary heat sink 2 of the packaging auxiliary equipment, and the boss 203 is located in the fourth groove 205, with adhesive filled between them. Each of the third grooves 202 corresponds to a bar 6, and the height of the bar array is greater than the depth of the second groove 201, that is, the bar array protrudes above the second groove 201. The space left between the boss 203 and the fourth groove 205 is filled with adhesive to improve the connection strength between the bar array and the secondary heat sink 2.

[0045] (3) Assemble and connect the integrated L-shaped electrode 3, the first insulating sheet 4, and the second insulating sheet 5 to their corresponding positions as described above, and clamp them in place with a fixture. Connect the end of the horizontal plate 302 to the outermost primary heat sink 7 of the bar array. Each side of the bar array is provided with an electrode structure consisting of the integrated L-shaped electrode 3, the first insulating sheet 4, and the second insulating sheet 5. Solder (such as indium silver or SAC305) is placed between the first insulating sheet 4, the second insulating sheet 5 and the integrated L-shaped electrode 3, and solder (such as indium silver or SAC305) is also placed between the first insulating sheet 4, the second insulating sheet 5 and the outer wall of the cooler 1. Then, the assembly is placed in a vacuum eutectic furnace for sintering, resulting in a packaged semiconductor laser.

[0046] Finally, it should be noted that any modifications, equivalent substitutions, or improvements made within the spirit and principles of this invention should be included within the scope of protection of this invention. Although specific embodiments of this invention have been described above in conjunction with the accompanying drawings, this is not intended to limit the scope of protection of this invention. Those skilled in the art should understand that various modifications or variations that can be made by those skilled in the art without creative effort based on the technical solutions of this invention are still within the scope of protection of this invention.

Claims

1. A high-efficiency packaging auxiliary device for semiconductor lasers, characterized in that, include: A cooler having a first groove on its upper surface for accommodating a secondary heat sink; The secondary heat sink has a second groove on its upper surface, and a plurality of third grooves arranged at intervals and parallel to each other in the second groove. The bottom surface of the second groove between adjacent third grooves has a boss, and both ends of the secondary heat sink have openings arranged parallel to the second groove. An integrated L-shaped electrode comprises an "L"-shaped plate, a horizontal plate, and a vertical plate; wherein: The "L"-shaped plate is vertically arranged and is used to cover the outer wall of the cooler, with the two being isolated and insulated from each other by a first insulating sheet; The horizontal plate is horizontally connected to the top of the "L"-shaped plate. The horizontal plate is used to be set on the upper surface of the cooler and the two do not contact each other. The end of the horizontal plate is located in the second groove adjacent to it after passing through the opening. The vertical plate is vertically connected to the lower end of the "L"-shaped plate. The vertical plate is used to cover the outer side wall of the cooler and the two are isolated and insulated by a second insulating sheet. The first insulating sheet and the second insulating sheet are located on two adjacent side walls.

2. The high-efficiency packaging auxiliary equipment for semiconductor lasers according to claim 1, characterized in that, The cooler has an inner cavity and an inlet and an outlet communicating with the inner cavity on its bottom surface.

3. The high-efficiency packaging auxiliary equipment for semiconductor lasers according to claim 2, characterized in that, The cooler includes a base and a cover plate; wherein: the base has an inner cavity and an opening on the upper surface, and the liquid inlet and liquid outlet are located on the bottom surface of the base; the cover plate covers the opening on the upper surface of the base to form a seal, and the lower surface of the cover plate has a plurality of heat dissipation columns located in the inner cavity of the base.

4. The high-efficiency packaging auxiliary equipment for semiconductor lasers according to claim 1, characterized in that, The end of the horizontal plate is supported on the upper surface of the secondary heat sink in the opening, so that a gap is formed between the horizontal plate and the cooler to insulate them.

5. The high-efficiency packaging auxiliary equipment for semiconductor lasers according to claim 1, characterized in that, The two outer side walls and the top surface of the boss have a conductive layer; optionally, the material of the conductive layer includes either gold or copper.

6. The high-efficiency packaging auxiliary equipment for semiconductor lasers according to claim 1, characterized in that, The secondary heat sink is a boron nitride insulating sheet.

7. The high-efficiency packaging auxiliary equipment for semiconductor lasers according to any one of claims 1-6, characterized in that, Optionally, the integrated L-shaped electrode is formed by gold plating on a brass surface.

8. A high-efficiency packaging method for semiconductor lasers, characterized in that, Includes the following steps: (1) A plurality of bar strips and strip-shaped primary heat sinks are arranged in an alternating manner and sintered together to form a bar strip array, wherein the bottom of the connecting surface between adjacent primary heat sinks has a fourth groove that matches the boss of the packaging auxiliary device according to any one of claims 1-7. (2) The bar array is embedded and fixed in the second groove of the secondary heat sink of the packaging auxiliary equipment, and the boss is located in the fourth groove, and adhesive is filled between the two; each of the third grooves corresponds to a bar; (3) Assemble the integrated L-shaped electrode, the first insulating sheet, and the second insulating sheet at the corresponding positions and fix them with clamps, and make contact connection between the end of the horizontal plate and the outermost primary heat sink of the bar array; set an electrode structure composed of the integrated L-shaped electrode, the first insulating sheet, and the second insulating sheet on each side of the bar array; wherein, solder is provided between the integrated L-shaped electrode, the cooler, and the first insulating sheet and the second insulating sheet; finally, sintering is performed to obtain the packaged semiconductor laser.

9. The high-efficiency packaging method for semiconductor lasers according to claim 8, characterized in that, In step (1), a groove is provided at a lower corner of the primary heat sink along its length, and the grooves of adjacent primary heat sinks form the fourth groove.

10. The high-efficiency packaging method for semiconductor lasers according to claim 8 or 9, characterized in that, In step (2), the height of the bar array is greater than the depth of the second groove.

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