Semiconductor laser device, and manufacturing method of heat sink

Abstract

To provide a semiconductor laser device capable of increasing reliability by suppressing erosion and corrosion in a fluid channel of an MC-type heat sink, and a manufacturing method of heat sink.SOLUTION: The semiconductor laser device is a semiconductor laser device that has a microchannel heat sink and a semiconductor laser element mounted on the heat sink. The heat sink has a fluid channel that is formed of at least three metal plates which are laminated and bonded, and the walls of the fluid channel are covered with a bimetallic alloy layer consisting of the base metal of the metal plate and the plating metal.SELECTED DRAWING: Figure 2

Description

[Technical field]

[0001] The present disclosure relates to a semiconductor laser device equipped with a microchannel type heat sink and a method for manufacturing the heat sink. [Background technology]

[0002] Conventionally, microchannel type heat sinks have been known as cooling devices (heat sinks) that are essential for cooling heat generating bodies such as high-output semiconductor laser elements (hereinafter referred to as "MC type heat sinks"). MC type heat sinks have fluid channels formed by laminating and bonding metal plates such as copper plates, and cool the heat generating body by circulating cooling water through these fluid channels.

[0003] In the MC type heat sink, for example, comb-shaped fluid channels are formed by stacking and bonding metal plates with fine grooves and holes. The comb-shaped fluid channels are very thin, and by increasing the number of fluid channels, the heat transfer area is increased, improving the heat conversion efficiency. Copper plates are mainly used as metal plates for MC type heat sinks because of their excellent thermal conductivity and workability.

[0004] Conventionally, in order to prevent corrosion in the fluid channels of MC type heat sinks, it has been proposed to form an isolation layer such as a precious metal film or a non-conductive film (oxide film) on the inner wall surface of the metal plate material (see, for example, Patent Documents 1 and 2). Corrosion is a phenomenon in which rust occurs due to the movement of free electrons in metal. In an environment such as a fluid channel where the free electrons in metal are likely to combine with water or acid, corrosion is likely to occur, and the corrosion is rapidly accelerated when electricity flows. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] JP 2003-273441 A [Patent Document 2] JP 2012-19086 A Summary of the Invention [Problem to be solved by the invention]

[0006] In Patent Documents 1 and 2, the isolation layer is used to prevent corrosion, but in the MC type heat sink, the fluid channels are minute and complex, so there is a problem of erosion (mechanical wear) as well as corrosion. Erosion is a phenomenon in which the fluid channels are scraped away by the flow of the cooling medium (e.g., water).

[0007] Specifically, in the fluid channels of an MC-type heat sink, the oxide film is peeled off by erosion starting from damaged areas or areas with rough surfaces. When the newly formed metal surface comes into contact with water, corrosion occurs. The corrosion penetrates into the metal, and the oxides that are generated precipitate and accumulate on the surface. The accumulated oxides are peeled off by erosion. If erosion and corrosion are repeated alternately in this way, there is a risk that the fluid channels will be damaged. Furthermore, if the peeled off oxides accumulate in the fluid channels and cause clogging, the heat exchange efficiency will decrease, which may affect the reliability of the semiconductor laser device.

[0008] An object of the present disclosure is to provide a semiconductor laser device and a method for manufacturing a heat sink that can suppress erosion and corrosion in the fluid channels of an MC type heat sink and improve reliability. [Means for solving the problem]

[0009] The semiconductor laser device according to the present disclosure comprises: A microchannel type heat sink; a semiconductor laser element mounted on the heat sink; A semiconductor laser device comprising: The heat sink has a fluid channel formed by laminating and bonding at least three metal plates, The wall surface of the fluid channel is covered with a two-metal alloy layer consisting of the base metal of the metal plate and the plating metal.

[0010] A method for manufacturing a heat sink according to the present disclosure includes: A method for manufacturing a microchannel type heat sink having a fluid channel therein, comprising the steps of: plating a plurality of metal sheets; A step of stacking and bonding a plurality of the metal plates; and forming an alloy layer consisting of the base metal of the metal plate and the plating metal. Effect of the Invention

[0011] According to the present disclosure, erosion and corrosion in the fluid channels of the MC type heat sink are suppressed, thereby improving the reliability of the semiconductor laser device. [Brief description of the drawings]

[0012] [Figure 1] 1A and 1B are perspective views showing a schematic configuration of a semiconductor laser device according to an embodiment. [Diagram 2] FIG. 2 is a diagram showing a cross-sectional configuration of the heat sink according to the first embodiment. [Diagram 3] 3A and 3B are exploded perspective views of the heat sink according to the first embodiment. [Figure 4] FIG. 4 is a diagram showing a cross-sectional configuration of a heat sink according to the second embodiment. [Diagram 5] 5A and 5B are exploded perspective views of a heat sink according to a second embodiment. [Figure 6] 6A and 6B are diagrams showing another example of the manufacturing process of the heat sink according to the second embodiment. [Figure 7] FIG. 7 is a diagram showing a cross-sectional configuration of a heat sink 1C according to the third embodiment. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0013] Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

[0014] [First embodiment] 1A and 1B are perspective views showing a schematic configuration of a semiconductor laser device 100 according to an embodiment. In Fig. 1B, a P electrode block 4 and an N electrode block 5 are shown in exploded form.

[0015] As shown in FIGS. 1A and 1B, a semiconductor laser device 100 includes a heat sink 1, a semiconductor laser element 2, a submount 3, a P-electrode block 4, and an N-electrode block 5.

[0016] The semiconductor laser element 2 is, for example, an array-type laser element having a plurality of light-emitting points. The semiconductor laser element 2 is mounted on a submount 3 for thermal conduction and stress relaxation, and then mounted on the heat sink 1. The submount 3 is joined, for example, by soldering to an outer layer plating (not shown) formed on the surface of the heat sink 1 (the upper surface of the first layer 11, see FIG. 2).

[0017] For example, nickel-gold plating can be used for the outer layer plating. Nickel-gold plating is preferable because it can electrically connect the semiconductor laser element 2, the P electrode block 4, and the N electrode block 5 using Au bumps or Au wires, and has good plating properties with respect to copper, which is the base metal of the metal plate 10 of the heat sink 1.

[0018] Fig. 2 is a diagram showing a cross-sectional configuration of the heat sink 1A according to the first embodiment. Figs. 3A and 3B are exploded perspective views of the heat sink 1A. Figs. 3A and 3B show the state before the alloy layer 22 is formed by heat treatment.

[0019] The heat sink 1A is an MC type heat sink having a microstructure of fluid channels 30. The heat sink 1A has a structure in which at least three or more thin metal plates 10 are laminated and joined together. In this embodiment, the heat sink 1A is composed of a laminated structure of five metal plates 11-15.

[0020] In the following, when distinguishing between the metal plates 11 to 15, they will be described as first layer plate 11, second layer plate 12, third layer plate 13, fourth layer plate 14, and fifth layer plate 15, in that order from the mounting surface side (the upper side in Figure 2) on which the semiconductor laser element 2 is mounted.

[0021] By stacking the metal plates 11-15, a fluid channel 30 is formed inside the heat sink 1A. The fluid channel 30 has a supply channel 31, a main channel 32, and a drain channel 33. The supply channel 31 is a channel for introducing the cooling medium toward the main channel 32. The main channel 32 is a channel for spreading the cooling medium two-dimensionally over the entire surface of the heat sink 1A. The drain channel 33 is a channel for discharging the cooling medium from the main channel 32.

[0022] The metal plates 11 to 15 are all formed of the same metal material. The base metal of the metal plates 11 to 15 preferably has high thermal conductivity and is easy to process, and is preferably, for example, copper (Cu).

[0023] The semiconductor laser element 2 and the submount 3 are mounted on the front surface of the first layer plate 11. An outer layer plating (not shown) is formed on the front surface of the first layer plate 11. The rear surface of the first layer plate 11 forms a part of the wall surface of the fluid channel 30.

[0024] The second layer plate 12 to the fifth layer plate 15 have openings for forming the fluid channels 30. These openings are formed by, for example, etching, electric discharge machining, die machining, or machining.

[0025] Specifically, the second layer 12 has an opening 121 that forms the main water channel 32. The side surface of the opening 121 forms the wall surface of the fluid channel 30. The opening 121 includes a comb-tooth forming portion 122 that forms a comb-tooth shaped water channel. The comb-tooth forming portion 122 is disposed at a position corresponding to a lower portion of the mounting position of the semiconductor laser element 2. With the metal plates 11-15 in a stacked and joined state, the opening 121 is closed by the rear surface of the first layer 11, thereby forming the main water channel 32.

[0026] The third layer 13 has an opening 131 forming the water supply channel 31 and an opening 132 forming the water drain channel 33. The sides of the openings 131 and 132 form the wall surfaces of the fluid channel 30. When the metal plates 11 to 15 are stacked and joined, the opening 131 communicates with the opening 121 of the second layer 12 and the opening 141 of the fourth layer 14. A plurality of openings 131 are provided so as to communicate with each of the comb-shaped channels formed by the second layer 12. When the metal plates 11 to 15 are stacked and joined, the opening 132 communicates with the opening 121 of the second layer 12 and the opening 142 of the fourth layer 14. The opening 132 is provided on the opposite side of the opening 131 in the longitudinal direction of the heat sink 1A.

[0027] The fourth layer 14 has an opening 141 which forms the water supply channel 31 and an opening 142 which forms the water drain channel 33. The sides of the openings 141, 142 form the wall surfaces of the fluid channel 30. When the metal plates 11 to 15 are stacked and joined, the opening 141 communicates with the opening 131 of the third layer 13 and the opening 151 of the fifth layer 15. When the metal plates 11 to 15 are stacked and joined, the opening 142 communicates with the opening 132 of the third layer 13 and the opening 152 of the fifth layer 15.

[0028] The fifth layer 15 has an opening 151 which forms the water supply channel 31 and an opening 152 which forms the drainage channel 33. When the metal plates 11 to 15 are stacked and joined together, the opening 151 communicates with the opening 141 of the fourth layer 14. When the metal plates 11 to 15 are stacked and joined together, the opening 152 communicates with the opening 142 of the fourth layer 14.

[0029] In the fluid channel 30, the surface in contact with the cooling medium (the wall surface of the fluid channel 30) is covered with an alloy layer 22. The alloy layer 22 is a binary metal composed of the base metal of the metal plates 11-15 and the plating metal of the plating layer 21. The alloy layer 22 is formed, for example, by sintering (heat treating) the base metal of the metal plates 11-15 and the plating metal of the plating layer 21 at 800°C to 1000°C.

[0030] Here, in order to plate the parts of the metal plates 11-15 that form the fluid channel 30 and form the alloy layer 22 consisting of the base metal and plating metal of the metal plates 11-15, it is necessary for one of the base metal and plating metal to melt. When one metal melts, particles of the other metal diffuse into the melt, and the diffused metal particles melt at a temperature exceeding the liquidus of the molten metal. For example, in the case of two types of metals that have a eutectic point, particles of the other metal diffuse into the molten metal and melt, approaching the eutectic point. As a result, the liquidus line drops, and when it falls below the solidus line of these metals, an alloy is formed.

[0031] A metal material having a lower melting point than the base metal is selected for the plating metal. This is because if the base metal of the metal plates 11-15 melts, it will be impossible to form a heat sink. For example, if the base metal of the metal plates 11-15 is copper (melting point: 1084°C), it is possible to use aluminum (melting point: 660°C) or tin (melting point: 231°C) for the plating metal. However, the combination of aluminum and copper is not preferred from the viewpoint of plating ability, and the combination of tin and copper is not preferred from the viewpoint of wear resistance.

[0032] On the other hand, the combination of copper and nickel is easy to plate, and since the alloy layer 22 is formed as a proportional solid solution, it also has excellent wear resistance. An all proportional solid solution is a solid solution in which all the components dissolve in any concentration in both the liquid and solid phases. Therefore, in this embodiment, nickel is used as the plating metal for forming the plating layer 21.

[0033] Generally, in order to form a pinhole-free plating layer 21, the thickness of the plating layer 21 needs to be 2 μm or more. Considering the formation of an alloy with the base metal of the metal plates 11-15, the thickness of the plating layer 21 is preferably 1 μm to 10 μm.

[0034] In the heat sink 1A, the cooling medium is introduced through a water supply port (opening 151) of the fifth layer panel 15, passes through a water supply channel 31, a main water channel 32 and a drain channel 33, and is drained through a drain port (opening 152) of the fifth layer panel 15.

[0035] Heat generated from the semiconductor laser element 2 is transferred to the heat sink 1A from the first layer plate 11 side. This heat is converted into heat by the cooling medium flowing through a comb-shaped water channel provided at a position corresponding to the semiconductor laser element 2. This cools the semiconductor laser element 2.

[0036] The heat sink 1A according to the first embodiment is manufactured, for example, as follows.

[0037] First, predetermined openings are formed in metal plate 10 having a thickness of 0.2 to 1 mm by etching, electric discharge machining, mold machining, machining, or the like to prepare first layer 11 to fifth layer 15. In the first embodiment, plating layer 21 made of nickel is formed on the entire surface of first layer 11 to fifth layer 15 to a thickness of 2 to 5 μm.

[0038] Next, the first layer 11 to the fifth layer 15 are laminated and bonded together. For example, solid-phase diffusion bonding can be used as the bonding method. Solid-phase diffusion bonding is a technique in which metals to be bonded are heated and pressurized to promote the movement of atoms at the bonding interface, and the materials to be bonded are bonded in a solid state without melting them. For example, first layer 11 to fifth layer 15 are aligned and stacked, then placed in a high-temperature (below the melting point of the metal) furnace and pressurized at high pressure (for example, several to tens of MPa), thereby performing solid-state diffusion bonding.

[0039] In solid-phase diffusion bonding, since no pressure is applied to the portions of the first to fifth layer plates 11 to 15 that form the fluid channels 30, an alloy layer 22 is formed that is a complete solid solution of the base metal copper and the plating metal nickel. By setting the heating temperature to 800°C to 1000°C or lengthening the heating time, the plating layer 21, which is 2 to 5 μm thick, can be entirely alloyed with the base metal to form the alloy layer 22 at the same time as the first to fifth layer plates 11 to 15 are laminated and bonded. In this manner, the heat sink 1A according to the first embodiment is completed.

[0040] Brazing, soldering, or the like may be used to join first layer 11 to fifth layer 15. After first layer 11 to fifth layer 15 are aligned and stacked and joined, they may be heated at 800° C. to 1000° C. to form alloy layer 22.

[0041] Thus, the semiconductor laser device 100 according to the first embodiment has the following characteristics either alone or in any suitable combination.

[0042] That is, the semiconductor laser device 100 according to the first embodiment is a semiconductor laser device including a microchannel type heat sink 1A and a semiconductor laser element 2 mounted on the heat sink 1A, the heat sink 1A has a fluid water passage 30 formed by laminating and bonding at least three or more metal plates 10, and the wall surface of the fluid water passage 30 is covered with a two-metal alloy layer consisting of the base metal and plating metal of the metal plate 10. Specifically, the base metal is copper, and the plating metal is nickel.

[0043] The semiconductor laser device 100 equipped with the heat sink 1A can suppress not only corrosion but also erosion (mechanical wear) compared to the case where the fluid channel 30 is covered with a passivation film or precious metal plating. Therefore, the reliability of the semiconductor laser device 100 is significantly improved.

[0044] In the semiconductor laser device 100 according to the first embodiment, the multiple metal plates 10 have grooves or openings, and by joining the multiple metal plates 10 together, the grooves or openings of the metal plates 10 adjacent to each other in the stacking direction are connected to each other to form the fluid channels 30. This makes it possible to easily create the microstructured fluid channels 30 inside the heat sink 1A.

[0045] In the semiconductor laser device 100 according to the first embodiment, the fluid channel 30 has a comb-shaped channel disposed in correspondence with the mounting position of the semiconductor laser element 2. This allows the heat generated in the semiconductor laser element 2 to be efficiently converted into heat, thereby cooling the semiconductor laser device 100.

[0046] The manufacturing method of the heat sink 1A includes a step of plating a plurality of metal plates 10, a step of stacking and bonding the plurality of metal plates 10, and a step of forming an alloy layer made of the base metal of the metal plates 10 and the plating metal. Specifically, the plating layer 21 is formed on the entire surface of the metal plates 10, the plurality of metal plates 10 are bonded, and then the alloy layer is formed (for example, by brazing or soldering). Alternatively, the plating layer 21 may be formed on the entire surface of the metal plates 10, and the alloy layer 22 may be formed simultaneously with bonding of the metal plates 10 (for example, by solid-state diffusion bonding).

[0047] According to the manufacturing method of the heat sink 1A, the alloy layer 22, which is advantageous in suppressing corrosion and erosion, can be easily formed with stable quality on the wall surface of the fluid channel having a fine structure.

[0048] [Second embodiment] Fig. 4 is a diagram showing a cross-sectional configuration of a heat sink 1B according to a second embodiment. Figs. 5A and 5B are exploded perspective views of the heat sink 1B. Figs. 5A and 5B show the state after an alloy layer 22 is formed by heat treatment. The same reference numerals are used for the same or corresponding components as those in the first embodiment, and descriptions thereof will be omitted as appropriate.

[0049] In the first embodiment, the plating layer 21 is formed on the entire surfaces of the metal plates 11-15, and the portions of the plating layer 21 that form the fluid channels 30 are alloyed. In contrast, in the second embodiment, the plating layer 21 is formed only on the portions of the metal plates 11-15 that form the fluid channels 30, and the entire plating layer 21 that is formed is alloyed.

[0050] The heat sink 1B according to the second embodiment is manufactured, for example, as follows.

[0051] First, predetermined openings are formed in metal plate 10 having a thickness of 0.2 to 1 mm by etching, electric discharge machining, mold machining, machining, or the like to prepare first layer plate 11 to fifth layer plate 15. In the second embodiment, first layer plate 11 to fifth layer plate 15 are masked so that only the portions forming fluid channels 30 are exposed. In second layer plate 12, only openings 121 form fluid channels 30, and the plate surface does not form fluid channels, so that openings 121 may be formed after masking the entire surface. The same applies to fourth layer plate 14.

[0052] Next, a plating layer 21 made of nickel is formed to a thickness of 2 to 5 μm on the portions of the first layer 11 to the fifth layer 15 that are exposed from the mask. The plating layer 21 is formed only on the portions of the first layer 11 to the fifth layer 15 that will become the wall surfaces of the fluid channel 30.

[0053] Next, the first layer 11 to the fifth layer 15 are each heated (sintering process) at, for example, 800°C to 1000°C while still masked. As a result, a copper-nickel alloy layer 22 is formed only on the portion that will become the wall surface of the fluid channel 30 (see Figs. 5A and 5B).

[0054] Next, the masking is removed, and the first layer 11 to the fifth layer 15 are laminated and bonded. Since the first layer 11 to the fifth layer 15 are bonded to each other using the same base metal, they can be bonded by solid-state diffusion bonding, brazing, soldering, etc. In this manner, the heat sink 1B according to the second embodiment is completed.

[0055] In addition, if there is a concern that other metals such as the base metal or solder may be exposed at the corners of the wall surface that will become the fluid channel 30 due to misalignment of the first layer 11 to the fifth layer 15, the masking shape may be provided with an overlapping margin so that the plating layer 21 overlaps the corners of the wall surface that will become the fluid channel 30.

[0056] The heat sink 1B according to the second embodiment can also be manufactured as follows: Figures 6A and 6B are diagrams showing another example of the manufacturing process for the heat sink 1B according to the second embodiment.

[0057] That is, as shown in Figures 6A and 6B, after bonding multiple sheets of first layer 11 to fifth layer 15, plating layer 21 may be formed and alloyed, and the laminated structure having alloy layer 22 formed thereon may be bonded.

[0058] 6A and 6B, the first layer 11 and the second layer 12 are laminated and bonded together, and then the second layer 12 is masked, and then a plating layer 21 is formed and alloyed. The fourth layer 14 and the fifth layer 15 are laminated and bonded together, and then a plating layer 21 is formed and alloyed. Then, a first laminate structure consisting of the first layer 11 and the second layer 12 is bonded to a second laminate structure consisting of the third layer 13 and the fourth layer 14 and the fifth layer 15.

[0059] 6A and 6B, there is no need to mask the first layer 11 and the fifth layer 15. In addition, since the plating layer 21 is formed and alloyed in a state where a part of the fluid channel 30 is formed by joining a plurality of metal plates 10, an alloy layer 22 of stable quality is formed even in the corners of the fluid channel 30. Therefore, the effect against corrosion and erosion is improved.

[0060] Thus, the semiconductor laser device 100 according to the second embodiment has the following characteristics either alone or in any suitable combination.

[0061] That is, the semiconductor laser device 100 according to the second embodiment is a semiconductor laser device including a microchannel type heat sink 1B and a semiconductor laser element 2 mounted on the heat sink 1B, the heat sink 1B has a fluid water passage 30 formed by laminating and bonding at least three or more metal plates 10, and the wall surface of the fluid water passage 30 is covered with a binary metal alloy layer consisting of the base metal and plating metal of the metal plate 10. Specifically, the base metal is copper, and the plating metal is nickel.

[0062] The semiconductor laser device 100 including the heat sink 1B can suppress not only corrosion but also erosion (mechanical wear) compared to the case where the fluid channel 30 is covered with a passivation film or precious metal plating. Therefore, the reliability of the semiconductor laser device 100 is significantly improved.

[0063] In the semiconductor laser device 100 according to the second embodiment, the multiple metal plates 10 have grooves or openings, and by joining the multiple metal plates 10 together, the grooves or openings of the metal plates 10 adjacent to each other in the stacking direction are connected to each other to form the fluid channels 30. This makes it possible to easily create the fluid channels 30 with a fine structure inside the heat sink 1B.

[0064] In the semiconductor laser device 100 according to the second embodiment, the fluid channel 30 has a comb-shaped channel disposed in correspondence with the mounting position of the semiconductor laser element 2. This allows the heat generated in the semiconductor laser element 2 to be efficiently converted into heat to cool the semiconductor laser device 100.

[0065] The method for manufacturing the heat sink 1B includes a step of plating the metal plates 10, a step of stacking and joining the metal plates 10, and a step of forming an alloy layer made of the base metal of the metal plates 10 and the plating metal. Specifically, a plating layer 21 is formed on the portion of the metal plates 10 where the fluid channels 30 are to be formed, an alloy layer 22 is formed, and then the metal plates 10 are joined. Alternatively, the metal plates 10 may be divided into a plurality of groups that are continuous in the stacking direction, the metal plates 10 are joined in groups to form a stacked structure, and then a plating layer may be formed on the portion where the fluid channels 30 are to be formed, and the stacked structures may be joined.

[0066] According to the manufacturing method of the heat sink 1B, the alloy layer 22, which is advantageous in suppressing corrosion and erosion, can be easily formed with stable quality on the wall surface of the fluid channel of the microstructure. Also, in the second embodiment, since the alloy layer 22 is formed before joining the metal plate 10, the metal plate 10 can be joined at a lower temperature than the sintering process, and brazing, soldering, etc. can be applied.

[0067] [Third embodiment] 7 is a diagram showing a cross-sectional configuration of a heat sink 1C according to a third embodiment. Components that are the same as or correspond to those in the first embodiment are given the same reference numerals, and descriptions thereof will be omitted as appropriate.

[0068] In the heat sink 1C, the first layer 11 and the fifth layer 15 are configured as a composite substrate 40 in which a metal layer 41 is formed on the front and back surfaces of an insulating layer 42. The composite substrate 40 is, for example, a DBC substrate (DBC: Direct Bonded Copper) in which copper plates are directly bonded to both sides of a ceramic substrate. For example, aluminum nitride (AlN) or silicon carbide (SiC), which have excellent thermal conductivity, is used for the ceramic substrate.

[0069] The fluid channel 30 formed inside the heat sink 1C is electrically insulated from the semiconductor laser element 2 by the first layer 11. That is, the heat sink 1C has a structure in which electricity from the semiconductor laser element 2 does not flow into the fluid channel 30 or the cooling medium. Therefore, it is possible to prevent corrosion from being accelerated by electricity, and this structure is more advantageous against corrosion.

[0070] Furthermore, when the first layer 11 is made of a DBC substrate, the linear expansion coefficient approaches that of the semiconductor laser element 2, so that the effects of mounting stress on the characteristics and bonding reliability of the semiconductor laser device 100 can be suppressed.

[0071] Furthermore, when the fifth layer board 15 is made of a DBC substrate, the plating layer 21 is preferably formed by electrolytic plating. If the plating layer 21 is formed by electroless plating, the end face of the insulating layer 42 is also plated, and there is a risk that the plating will peel off and obstruct the flow of the cooling medium in the fluid channel 30.

[0072] The heat sink 1C according to the third embodiment can be manufactured by, for example, the same manufacturing method as that for the heat sink 1A according to the first embodiment.

[0073] It is sufficient that at least the first layer board 11 is made of the composite substrate 40, and the fifth layer board 15 may be a metal plate. However, it is preferable that both the first layer board 11 and the fifth layer board 15 are made of the composite substrate 40 so that the heat sink 1C does not warp or deform.

[0074] In addition, in the third embodiment, the first layer 11 and the fifth layer 15 in the heat sink 1A of the first embodiment are described as being made of a composite substrate, but the first layer 11 and the fifth layer 15 in the heat sink 1B of the second embodiment can also be made of a composite substrate.

[0075] As described above, the semiconductor laser device 100 according to the third embodiment has the following characteristics either alone or in any suitable combination.

[0076] That is, the semiconductor laser device 100 according to the third embodiment is a semiconductor laser device including a microchannel type heat sink 1C and a semiconductor laser element 2 mounted on the heat sink 1C, the heat sink 1C has a fluid water passage 30 formed by laminating and bonding at least three or more metal plates 10, and the wall surface of the fluid water passage 30 is covered with a two-metal alloy layer consisting of the base metal and plating metal of the metal plate 10. Specifically, the base metal is copper, and the plating metal is nickel.

[0077] The semiconductor laser device 100 equipped with the heat sink 1C can suppress not only corrosion but also erosion (mechanical wear) compared to the case where the fluid channel 30 is covered with a passivation film or precious metal plating. Therefore, the reliability of the semiconductor laser device 100 is significantly improved.

[0078] In the semiconductor laser device 100 according to the third embodiment, the multiple metal plates 10 have grooves or openings, and by joining the multiple metal plates 10 together, the grooves or openings of the metal plates 10 adjacent to each other in the stacking direction are connected to each other to form the fluid channels 30. This makes it possible to easily create the fluid channels 30 with a fine structure inside the heat sink 1C.

[0079] In the semiconductor laser device 100 according to the third embodiment, the fluid channel 30 has a comb-shaped channel disposed in correspondence with the mounting position of the semiconductor laser element 2. This allows the heat generated in the semiconductor laser element 2 to be efficiently converted into heat, thereby cooling the semiconductor laser device 100.

[0080] In the semiconductor laser device 100 according to the third embodiment, among the three or more metal plates 10, the first layer plate 11 (the uppermost metal plate) on which the semiconductor laser element 2 is mounted is a composite substrate 40 in which a metal layer 41 is formed on the front and back surfaces of an insulating layer 42. This makes it possible to prevent the inflow of electricity from the semiconductor laser element 2 to the fluid channel 30 and the cooling medium, thereby improving corrosion resistance.

[0081] In the semiconductor laser device 100 according to the third embodiment, among the three or more metal plates 10, the fifth layer 15 (the lowermost metal plate) opposite the first layer 11 (the uppermost metal plate) is also a composite substrate 40 in which metal layers 41 are formed on the front and rear surfaces of an insulating layer 42. This makes it possible to prevent warping or deformation of the heat sink 1C due to the difference in thermal expansion coefficient between the first layer 11 and the fifth layer 15.

[0082] The present invention has been specifically described above based on the embodiment, but the present invention is not limited to the above embodiment and can be modified without departing from the gist of the invention. The scope of the present invention is indicated by the claims, not the above description, and is intended to include all modifications within the meaning and scope of the claims. [Industrial Applicability]

[0083] The semiconductor laser device according to the present disclosure is useful as a semiconductor component having an MC type heat sink with microstructured fluid channels. [Explanation of symbols]

[0084] 1, 1A, 1B, 1C Heatsink 2. Semiconductor laser element 3 Submount 10 metal plate 21 Plating layer 22 alloy layer 30 Fluid waterway 31 Water supply channel 32 Main waterway 33 Drainage Channel 40 Composite Board 41 Metal layer 42 Insulating layer 100 Semiconductor laser device

Claims

1. A microchannel type heat sink; a semiconductor laser element mounted on the heat sink; A semiconductor laser device comprising: The heat sink has a fluid channel formed by laminating and bonding at least three metal plates, The wall surface of the fluid channel is coated with a two-metal alloy layer consisting of the base metal of the metal plate and the plating metal. Semiconductor laser device.

2. The base metal is copper; The plating metal is nickel.

2. The semiconductor laser device according to claim 1.

3. The plurality of metal plates have grooves or openings, By joining a plurality of the metal plates, the grooves or openings of the metal plates adjacent to each other in the stacking direction are connected to each other, thereby forming the fluid channel.

3. The semiconductor laser device according to claim 1 or 2.

4. The fluid channel has a comb-shaped channel arranged corresponding to the mounting position of the semiconductor laser element.

4. The semiconductor laser device according to claim 3.

5. Among the three or more metal plates, the uppermost metal plate on which the semiconductor laser element is mounted is a composite substrate having metal layers formed on the front and back surfaces of an insulating layer.

3. The semiconductor laser device according to claim 1 or 2.

6. Among the three or more metal plates, the metal plate of the lowermost layer opposite to the metal plate of the uppermost layer is a composite substrate in which a metal layer is formed on the front and back surfaces of an insulating layer.

6. The semiconductor laser device according to claim 5.

7. A method for manufacturing a microchannel type heat sink having a fluid channel therein, comprising the steps of: plating a plurality of metal sheets; A step of stacking and bonding a plurality of the metal plates; forming an alloy layer consisting of a base metal of the metal plate and a plating metal; A method for manufacturing a heat sink comprising:

8. forming a plating layer on the entire surface of the metal plate, and forming the alloy layer after joining the plurality of metal plates or simultaneously with joining the metal plates; A method for manufacturing the heat sink according to claim 7.

9. forming a plating layer on a portion of the metal plate that will form the fluid channel, forming the alloy layer, and then bonding a plurality of the metal plates together; A method for manufacturing the heat sink according to claim 7.

10. Dividing the plurality of metal plates into a plurality of groups that are continuous in the stacking direction, joining the plurality of metal plates in units of the groups to form a laminated structure, forming a plating layer on a portion that forms the fluid channel, and joining the plurality of laminated structures; A method for manufacturing the heat sink according to claim 7.

Images