JP5307702B2 - heatsink - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a heat sink for cooling a semiconductor element which achieves sufficient corrosion resistance. <P>SOLUTION: A metal layer covering a plate-like part 5 includes: a part jointed to a metal layer covering a plate-like part 3 on the plate-like part 3 side; a part jointed to a metal layer covering a plate-like part 7 on the plate-like part 7 side; a part isolated from the metal layer covering the plate-like part 3 on a recessed part 3c located on the plate-like part 3 side and constituting a flow passage F; and a part isolated from the metal layer covering the plate-like part 7 on a recessed part 7c located on the plate-like part 7 side and constituting the flow passage F. A joint surface between the plate-like part 5 and the plate-like part 3 is a joint surface between AuSn solder layers, and a joint surface between the plate-like part 5 and the plate-like part 7 is a joint surface between the AuSn solder layers. The inner wall of the flow passage F is covered with the AuSn solder layers. <P>COPYRIGHT: (C)2011,JPO&amp;INPIT

Description

  The present invention relates to a heat sink for cooling a semiconductor element.

  Patent Document 1 discloses a semiconductor laser device and a heat sink for the purpose of preventing the generation of stress without reducing the exhaust heat efficiency. The heat sink of Patent Document 1 is configured by laminating a laser chip mounting plate, a heat radiation fin forming plate, a water channel forming plate, a heat radiation fin forming plate, and a water channel forming plate. A flow path through which the cooling liquid passes is formed inside the heat sink, and a semiconductor laser chip is mounted on the upper surface of the heat sink. The laser chip mounting plate constituting the entire upper surface of the heat sink is made of an insulating material such as ceramic having a thermal expansion coefficient close to that of the semiconductor laser chip. The radiating fin forming plate is made of, for example, copper which is a high thermal conductivity material in order to improve the exhaust heat effect. The water channel forming plate is made of the same material as that of the laser chip mounting plate in order to suppress the occurrence of warpage due to the difference in thermal expansion coefficient of each layer, and the heat sink is configured symmetrically in the stacking direction.

Patent Document 2 discloses that the semiconductor cooler is prevented from being distorted and that the semiconductor chip is prevented from being detached from the semiconductor cooler when the semiconductor chip and the semiconductor cooler are thermally expanded. The intended technique is disclosed. The semiconductor cooler of Patent Document 2 is for cooling a semiconductor chip, and includes at least an upper plate, an intermediate plate, and a lower plate, and includes an inlet portion, an outlet portion, and a flow path portion 1 for a cooling medium. Prepare. The upper plate and the lower plate are composite plates. This composite plate has a thickness on one or both sides of an auxiliary plate made of a material having a tensile strength of 1000 N / mm ² or more, a thermal conductivity of 100 W / m · K or more, and a thermal expansion coefficient of 6.0 ppm or less per degree Celsius. It is configured by applying a copper plating of 0.05 mm or more.

JP 2006-294943 A Japanese Patent Laying-Open No. 2005-217211 JP 2003-273441 A JP 2001-60736 A

  The heat sink according to the prior art is water-cooled, and a flow path for flowing cooling water is provided inside the heat sink. If water is allowed to flow inside the heat sink, there is a high possibility that corrosion will occur inside the heat sink. Therefore, sufficient corrosion resistance against water is required. In addition, when the heat sink has a configuration in which a plurality of plate-like members are stacked and includes a portion where two plate-like members made of different metals are joined, different metal joining interfaces Since corrosion may occur due to differences in ionization tendency, corrosion resistance at the joint interface is required. Therefore, the present invention is a heat sink for cooling a semiconductor element made in view of the above matters, and aims to realize sufficient corrosion resistance.

  One aspect of the heat sink of the present invention is a heat sink for cooling a semiconductor element, which is a plate-like first member made of a material having a low thermal expansion coefficient and a first metal that covers the first member. A first plate-like portion having a layer, a second copper-plate portion having a first copper plate portion and a second metal layer covering the first copper plate portion, a second copper-plate portion, and And a third plate-like portion having a third metal layer covering the second copper plate portion. The third plate-like portion, the first plate upper portion, and the second plate-like portion are laminated in order, and the second plate-like portion is a main surface on the first plate-like portion side. And the third plate-like portion has a second recess provided on a main surface on the first plate-like portion side, and the first plate-like shape is provided. The portion has a through hole communicating with the first recess and the second recess, and the first metal layer is formed of a first AuSn solder layer provided on a surface of the first metal layer. The second metal layer has a second AuSn solder layer provided on the surface of the second metal layer, and the third metal layer is formed on the surface of the third metal layer. A third AuSn solder layer provided; and the first metal layer has a portion joined to the second metal layer on the second plate-like portion side, and the third plate-like shape. On the part side A portion that is bonded to the metal layer, a portion that is on the second plate-like portion side and is separated from the second metal layer on the first concave portion, and the third plate-like shape And a portion separated from the third metal layer on the second concave portion, and a joining surface between the first plate-like portion and the second plate-like portion is: It is a joint surface between the first AuSn solder layer and the second AuSn solder layer, and the joint surface between the first plate-like portion and the third plate-like portion is the first AuSn solder layer. And the third AuSn solder layer.

  Therefore, since the first plate-like portion and the second plate-like portion, and the first plate-like portion and the third plate-like portion are all joined via AuSn solder, The joining surface is not a dissimilar metal interface, and thus corrosiveness at the dissimilar metal interface is avoided.

  In the above aspect relating to the heat sink of the present invention, the first metal layer includes a first Ni plating layer provided between the first member and the first AuSn solder layer, and a first An Au plating layer, and the second metal layer includes a second Ni plating layer and a second Au plating provided between the first copper plate portion and the second AuSn solder layer. A third Ni plating layer and a third Au plating layer provided between the second copper plate portion and the third AuSn solder layer. Can further be included.

  The first to third metal layers have a Ni plating layer and an Au plating layer under the AuSn solder layer. As described above, since the AuSn solder layer is formed on the plating layer containing Ni and Au, the corrosiveness generated at the interface between different metals is reduced at the joint surface with the AuSn solder layer.

  In the above aspect relating to the heat sink of the present invention, the second plate-like portion includes a plate-like second member made of a material having a low thermal expansion coefficient, a third copper plate portion, and the third copper plate portion. A fourth metal layer covering the first plate, and the third plate-shaped portion includes a plate-shaped third member made of a material having a low thermal expansion coefficient, a fourth copper plate portion, and the fourth plate. A fifth metal layer covering the copper plate portion, the second member is provided on the first copper plate portion via the second metal layer, and the third copper plate portion is , Provided on the second member via the fourth metal layer, and the third member is provided on the second copper plate portion via the third metal layer. The copper plate portion can be provided on the third member via the fifth metal layer.

  Since the third and fourth copper plate portions are further provided, heat can be efficiently discharged together with the first and second copper plate portions.

  In the above aspect relating to the heat sink of the present invention, the fourth metal layer includes a fourth Ni plating layer and a fourth Au plating layer, and the fifth metal layer includes a fifth Ni plating. And a fifth Au plating layer.

  The fourth and third metal layers have a Ni plating layer and an Au plating layer under the AuSn solder layer. As described above, since the AuSn solder layer is formed on the plating layer containing Ni and Au, the corrosiveness generated at the interface between different metals is reduced at the joint surface with the AuSn solder layer.

  ADVANTAGE OF THE INVENTION According to this invention, it can provide the heat sink which has sufficient corrosion resistance and cools a semiconductor element.

It is a disassembled perspective view which shows the structure of the heat sink which concerns on embodiment. It is a figure which shows the structure of the heat sink which concerns on embodiment. It is a figure for demonstrating the structure of the metal layer of the heat sink which concerns on embodiment. It is a perspective view which shows the structure of the semiconductor laser stack apparatus using the heat sink which concerns on embodiment. It is a figure which shows the structure of the semiconductor laser stack apparatus using the heat sink which concerns on embodiment. It is a perspective view which shows the structure of the semiconductor laser stack apparatus using the other heat sink which concerns on embodiment. It is a figure which shows the structure of the semiconductor laser stack apparatus using the other heat sink which concerns on embodiment. It is a figure which shows the structure of the other semiconductor laser stack apparatus using the other heat sink which concerns on embodiment.

  Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the drawings. In the description of the drawings, if possible, the same elements are denoted by the same reference numerals, and redundant description is omitted. FIG. 1 is an exploded perspective view showing a configuration of a heat sink according to the embodiment. The heat sink 1 is for cooling a semiconductor element (for example, the semiconductor laser element 11 shown in FIG. 4 and the like). The heat sink 1 includes a plate-like portion 3, a plate-like portion 5, and a plate-like portion 7. The plate-like portion 3 has a main surface 3d and a back surface 3e on the opposite side of the main surface 3d. The plate-like portion 5 has a surface 5d and a surface 5e opposite to the surface 5d. The plate-like portion 7 has a main surface 7d and a back surface 7e on the opposite side of the main surface 7d. The plate-like part 7, the plate-like part 5, and the plate-like part 3 are laminated in order. The plate-like part 3, the plate-like part 5, and the plate-like part 7 form a substantially rectangular parallelepiped in a stacked state. That is, the heat sink 1 has a substantially rectangular parallelepiped outer shape. The main surface 7d of the plate-like portion 7 and the surface 5e of the plate-like portion 5 are in contact, and the surface 5d of the plate-like portion 5 and the main surface 3d of the plate-like portion 3 are in contact.

  The plate-like portion 3 has a through hole 3a and a through hole 3b that penetrate from the main surface 3d to the back surface 3e. The plate-like portion 5 has a through hole 5a and a through hole 5b that penetrate from the surface 5d to the surface 5e. The plate-like portion 7 has a through hole 7a and a through hole 7b that penetrate from the main surface 7d to the back surface 7e. Each of the through hole 3a, the through hole 5a, and the through hole 7a has a cylindrical shape, and each central axis thereof overlaps the central axis AX1. The through-hole 3a, the through-hole 5a, and the through-hole 7a constitute a water supply path 9a that penetrates from the surface 1b of the heat sink 1 to the surface 1a (see FIG. 2). A cooling liquid (coolant) supplied from the outside flows through the water supply passage 9a. The through-hole 3b, the through-hole 5b, and the through-hole 7b all have a cylindrical shape, and each central axis overlaps the central axis AX2. The through hole 3b, the through hole 5b, and the through hole 7b constitute a drainage channel 9b that penetrates from the surface 1b of the heat sink 1 to the surface 1a (see FIG. 2). The drainage channel 9b is a pipe for discharging the coolant that has flowed into the heat sink 1 to the outside.

  The plate-like portion 3 has a concave portion 3c provided on the main surface 3d. The recess 3c is connected to the through hole 3b through the opening 3f. The recess 3c communicates with the through hole 3b but does not communicate with the through hole 3a. The plate-like portion 5 has a plurality of through holes 5c penetrating from the surface 5d to the surface 5e. The plate-like portion 7 has a concave portion 7c provided on the main surface 7d. The recess 7c is connected to the through hole 7a through the opening 7f. The recess 7c communicates with the through hole 7a, but does not communicate with the through hole 7b. The through hole 5c communicates with the recess 3c and the recess 7c.

  FIG. 2 shows a cross section of the heat sink 1. The cross section shown in FIG. 2 includes a central axis AX1 and a central axis AX2. As shown in FIG. 2, the plate-like part 3 has a plate-like part 31, a plate-like part 331, and a plate-like part 35, and the plate-like part 7 has a plate-like part 71, a plate-like part 731 and a plate. A shaped portion 75 is provided. The plate-shaped part 31, the plate-shaped part 331, and the plate-shaped part 35 are laminated | stacked in order, and comprise a substantially rectangular parallelepiped in the laminated | stacked state. That is, the plate-like portion 3 has a substantially rectangular parallelepiped outer shape. The plate-like part 75, the plate-like part 731 and the plate-like part 71 are laminated in order, and form a substantially rectangular parallelepiped in the laminated state. That is, the plate-like portion 7 has a substantially rectangular parallelepiped outer shape. The plate-like portion 75, the plate-like portion 731, the plate-like portion 71, the plate-like portion 5, the plate-like portion 31, the plate-like portion 331, and the plate-like portion 35 are laminated in order. The surface of the plate-like portion 35 is the surface 1 a of the heat sink 1, and the surface of the plate-like portion 75 is the surface 1 b of the heat sink 1. A plate-like portion 731 is provided on the plate-like portion 75, a plate-like portion 71 is provided on the plate-like portion 731, a plate-like portion 5 is provided on the plate-like portion 71, and a plate-like shape is provided on the plate-like portion 5. The plate portion 331 is provided on the plate portion 31, and the plate portion 35 is provided on the plate portion 331. In FIG. 2, the flow path of the coolant flowing through the heat sink 1 is indicated by an arrow F (hereinafter referred to as the flow path F). The plate-like portion 31 and the plate-like portion 71 have the same configuration except for the recess 3c and the recess 7c, and the plate-like portion 331 and the plate-like portion 731 have the same configuration. The shape portion 35 and the plate shape portion 75 have the same configuration.

  Next, with reference to FIG. 3, the structure of the plate-shaped part 31, the plate-shaped part 331, the plate-shaped part 35, the plate-shaped part 5, the plate-shaped part 71, the plate-shaped part 731 and the plate-shaped part 75 is demonstrated. The configuration of the plate-like portion 31 will be described with reference to FIG. The plate-like portion 31 includes a copper plate portion 31a and a metal layer 31g (Ni plating layer 31b, Au plating layer 31c, and AuSn solder layer 31d) that covers the copper plate portion 31a. The Ni plating layer 31b, the Au plating layer 31c, and the AuSn solder layer 31d are sequentially laminated on the surface of the copper plate portion 31a (including the end surface 31e of the plate-like portion 31 and the surface on the inner wall surface side of the recess 3c). Yes. The Ni plating layer 31b covers the surface of the copper plate portion 31a (including the end surface 31e of the copper plate portion 31a and the inner wall surface of the recess 3c) without exposing it, and the Au plating layer 31c is covered with the Ni plating layer 31b. The AuSn solder layer 31d covers the surface of the Au plating layer 31c without exposing it. The end surface 31e includes a surface of the copper plate portion 31a on the outer wall surface side of the plate-like portion 31, a surface of the copper plate portion 31a on the inner wall surface side of the water supply passage 9a (through hole 3a), and a drainage passage 9b (through hole 3b). Corresponds to the surface of the copper plate portion 31a on the inner wall surface side. The metal layer 31g is also provided on the end surface 31e. The AuSn solder layer 31d is provided on the surface of the metal layer 31g. The Ni plating layer 31b and the Au plating layer 31c are provided between the copper plate portion 31a and the AuSn solder layer 31d. A portion of the metal layer 31g provided on the end surface 31e forms a part of the outer wall surface of the heat sink 1, a part of the inner wall surface of the water supply channel 9a, and a part of the inner wall surface of the drainage channel 9b. The recess 3c is provided only in the plate-like portion 31, and the metal layer 31g particularly forms the inner wall surface of the recess 3c.

  With reference to FIG. 3D, the structure of the plate-like portion 331 will be described. The plate-like portion 331 includes a low thermal expansion coefficient member 331a and a metal layer 331g (Ni plating layer 331b, Au plating layer 331c, and AuSn solder layer 331d) that covers the low thermal expansion coefficient member 331a. The Ni plating layer 331b, the Au plating layer 331c, and the AuSn solder layer 331d are sequentially stacked on the portion of the surface of the low thermal expansion coefficient member 331a excluding the end surface 331e. That is, the metal layer 331g is not provided on the end surface 331e of the plate-shaped portion 331, and the surface on the outer wall surface side of the plate-shaped portion 331 among the surfaces of the low thermal expansion coefficient member 331a, the inside of the water supply channel 9a. It is provided only on the portion excluding the surface on the wall surface side and the surface on the inner wall surface side of the drainage channel 9b. The low thermal expansion coefficient member 331a is exposed on any of the outer wall surface, the inner wall surface of the water supply channel 9a, and the inner wall surface of the drainage channel 9b. The plate-like portion 331 is provided on the copper plate portion 31 a via the metal layer 31 g of the plate-like portion 31. The Ni plating layer 331b covers the surface of the low thermal expansion coefficient member 331a (the surface of the low thermal expansion coefficient member 331a excluding the end surface 331e), and the Au plating layer 331c covers the surface of the Ni plating layer 331b without exposing it. The AuSn solder layer 331d covers the surface of the Au plating layer 331c without exposing it. The end surface 331e includes a surface of the low thermal expansion coefficient member 331a on the outer wall surface side of the plate-shaped portion 331, a surface of the low thermal expansion coefficient member 331a on the inner wall surface side of the water supply channel 9a (through hole 3a), and a drainage channel 9b ( This corresponds to the surface of the low thermal expansion coefficient member 331a on the inner wall surface side of the through hole 3b). The AuSn solder layer 331d is provided on the surface of the metal layer 331g.

  With reference to FIG. 3 (B) and FIG. 3 (C), the structure of the plate-shaped part 35 is demonstrated. The plate-like portion 35 has a copper plate portion 35a and a metal layer 35g (Ni plating layer 35b, Au plating layer 35c and AuSn solder layer 35d) covering the copper plate portion 35a. The Ni plating layer 35b and the Au plating layer 35c are sequentially laminated on the surface of the copper plate portion 35a (including the end surface 35e and the end surface 35f of the copper plate portion 35a). The copper plate part 35a is provided on the plate-like part 331 (or the plate-like part 332) via the metal layer 35g. The Ni plating layer 35b covers the surface of the copper plate portion 35a (including the end surface 35e and the end surface 35f of the copper plate portion 35a) without exposing it, and the Au plating layer 35c covers the surface of the Ni plating layer 35b without exposing it. doing. The metal layer 35g is also provided on the end surface 35e and the end surface 35f of the copper plate portion 35a. The AuSn solder layer 35d is provided only on the end face 35f. On the end face 35f, a Ni plating layer 35b, an Au plating layer 35c, and an AuSn solder layer 35d are sequentially laminated. The end surface 35e corresponds to the surface of the copper plate portion 35a on the outer wall surface side of the plate-like portion 35, and the end surface 35f is the surface of the copper plate portion 35a on the inner wall surface side of the water supply channel 9a (through hole 3a), and , Corresponding to the surface of the copper plate portion 35a on the inner wall surface side of the drainage channel 9b (through hole 3b). The portion of the metal layer 35g provided on the end surface 35e forms a part of the outer wall surface of the heat sink 1, and the portion of the metal layer 35g provided on the end surface 35f is the inner wall surface of the water supply channel 9a, drainage It forms a part of the inner wall surface of the path 9b.

  A configuration of the plate-like portion 71 will be described with reference to FIG. The plate-like portion 71 has a copper plate portion 71a and a metal layer 71g (Ni plating layer 71b, Au plating layer 71c and AuSn solder layer 71d) covering the copper plate portion 71a. The Ni plating layer 71b, the Au plating layer 71c, and the AuSn solder layer 71d are sequentially laminated on the surface of the copper plate portion 71a (including the end surface 71e of the plate-like portion 71 and the surface on the inner wall surface side of the recess 7c). Yes. The Ni plating layer 71b covers the surface of the copper plate portion 71a (including the end surface 71e of the copper plate portion 71a and the inner wall surface of the recess 7c) without exposing it, and the Au plating layer 71c is covered with the Ni plating layer 71b. The AuSn solder layer 71d covers the surface of the Au plating layer 71c without exposing it. The end surface 71e includes the surface of the copper plate portion 71a on the outer wall surface side of the plate-like portion 71, the surface of the copper plate portion 71a on the inner wall surface side of the water supply channel 9a (through hole 7a), and the drainage channel 9b (through hole 7b). Corresponds to the surface of the copper plate portion 71a on the inner wall surface side. The metal layer 71g is also provided on the end surface 71e. The AuSn solder layer 71d is provided on the surface of the metal layer 71g. The Ni plating layer 71b and the Au plating layer 71c are provided between the copper plate portion 71a and the AuSn solder layer 71d. A portion of the metal layer 71g provided on the end surface 71e forms a part of the outer wall surface of the heat sink 1, a part of the inner wall surface of the water supply channel 9a, and a part of the inner wall surface of the drainage channel 9b. The concave portion 7c is provided only in the plate-like portion 71, and the metal layer 71g particularly forms the inner wall surface of the concave portion 7c.

  With reference to FIG. 3D, the structure of the plate-like portion 731 will be described. The plate-like portion 731 includes a low thermal expansion coefficient member 731a and a metal layer 731g (Ni plating layer 731b, Au plating layer 731c, and AuSn solder layer 731d) that covers the low thermal expansion coefficient member 731a. The Ni plating layer 731b, the Au plating layer 731c, and the AuSn solder layer 731d are sequentially stacked on the surface of the low thermal expansion coefficient member 731a except for the end face 731e. That is, the metal layer 731g is not provided on the end surface 731e of the plate-like portion 731. Of the surface of the low thermal expansion coefficient member 731a, the surface on the outer wall surface side of the plate-like portion 731, the inside of the water supply channel 9a. It is provided only on the portion excluding the surface on the wall surface side and the surface on the inner wall surface side of the drainage channel 9b. The low thermal expansion coefficient member 731a is exposed on any of the outer wall surface, the inner wall surface of the water supply channel 9a, and the inner wall surface of the drainage channel 9b. The plate-like part 731 is provided on the copper plate part 71 a via the metal layer 71 g of the plate-like part 71. The Ni plating layer 731b covers the surface of the low thermal expansion coefficient member 731a (the surface of the low thermal expansion coefficient member 731a excluding the end face 731e) without exposing it, and the Au plating layer 731c exposes the surface of the Ni plating layer 731b. The AuSn solder layer 731d covers the surface of the Au plating layer 731c without exposing it. The end surface 731e includes a surface of the low thermal expansion coefficient member 731a on the outer wall surface side of the plate-like portion 731, a surface of the low thermal expansion coefficient member 731a on the inner wall surface side of the water supply channel 9a (through hole 3a), and a drainage channel 9b ( This corresponds to the surface of the low thermal expansion coefficient member 731a on the inner wall surface side of the through hole 3b). The AuSn solder layer 731d is provided on the surface of the metal layer 731g.

  With reference to FIG. 3B and FIG. 3C, the configuration of the plate-like portion 75 will be described. The plate-like portion 75 includes a copper plate portion 75a and a metal layer 75g (Ni plating layer 75b, Au plating layer 75c, and AuSn solder layer 75d) that covers the copper plate portion 75a. The Ni plating layer 75b and the Au plating layer 75c are sequentially stacked on the surface of the copper plate portion 35a (including the end surface 75e and the end surface 75f of the copper plate portion 75a). The copper plate part 75a is provided on the plate-like part 731 (or the plate-like part 732) via the metal layer 75g. The Ni plating layer 75b covers the surface of the copper plate portion 75a (including the end surface 75e and the end surface 75f of the copper plate portion 75a) without exposing it, and the Au plating layer 75c covers the surface of the Ni plating layer 75b without exposing it. doing. The metal layer 75g is also provided on the end surface 75e and the end surface 75f of the copper plate portion 75a. The AuSn solder layer 75d is provided only on the end face 75f. On the end face 75f, a Ni plating layer 75b, an Au plating layer 75c, and an AuSn solder layer 75d are sequentially laminated. The end surface 75e corresponds to the surface of the copper plate portion 75a on the outer wall surface side of the plate-like portion 75, and the end surface 75f is the surface of the copper plate portion 75a on the inner wall surface side of the water supply channel 9a (through hole 3a), and Corresponds to the surface of the copper plate portion 75a on the inner wall surface side of the drainage channel 9b (through hole 3b). A portion of the metal layer 75g provided on the end surface 75e forms a part of the outer wall surface of the heat sink 1, and a portion of the metal layer 75g provided on the end surface 75f is an inner wall surface of the water supply channel 9a, drainage It forms a part of the inner wall surface of the path 9b.

  The configuration of the plate-like portion 5 will be described with reference to FIG. The plate-like portion 5 includes a plate-like low thermal expansion coefficient member 51a made of a material having a low thermal expansion coefficient, and a metal layer 51g (Ni plating layer 51b, Au plating layer 51c, and AuSn solder layer 51d) covering the low thermal expansion coefficient member 51a. And have. The Ni plating layer 51b, the Au plating layer 51c, and the AuSn solder layer 51d are sequentially stacked on the surface of the low thermal expansion coefficient member 51a (including the end surface 51e of the low thermal expansion coefficient member 51a). The Ni plating layer 51b covers the surface of the low thermal expansion coefficient member 51a (including the end surface 51e of the low thermal expansion coefficient member 51a) without exposing it, and the Au plating layer 51c does not expose the surface of the Ni plating layer 51b. The AuSn solder layer 51d is coated without exposing the surface of the Au plating layer 51c. The end surface 51e is the surface of the low thermal expansion coefficient member 51a on the outer wall surface side of the plate-like portion 5, the surface of the low thermal expansion coefficient member 51a on the inner wall surface side of the through hole 5c, and the inner wall surface of the water supply channel 9a (through hole 5a). It corresponds to the surface of the low thermal expansion coefficient member 51a on the side and the surface of the low thermal expansion coefficient member 51a on the inner wall surface side of the drainage channel 9b (through hole 5b). The metal layer 51g is also provided on the end face 51e. The AuSn solder layer 51d is provided on the surface of the metal layer 51g. The Ni plating layer 51b and the Au plating layer 51c are provided between the low thermal expansion coefficient member 51a and the AuSn solder layer 51d. A portion of the metal layer 51g provided on the end surface 51e forms a part of the outer wall surface of the heat sink 1, a part of the inner wall surface of the water supply channel 9a, and a part of the inner wall surface of the drainage channel 9b.

  This will be described with reference to FIGS. The AuSn solder layer 51d of the plate-like part 5 is joined to the AuSn solder layer 31d of the plate-like part 31 on the plate-like part 3 side (on the surface 5d), and is plate-like on the plate-like part 7 side (on the surface 5e). Bonded to the AuSn solder layer 71 d of the portion 71. The metal layer 51g includes a portion joined to the metal layer 31g on the plate-like portion 3 side, a portion joined to the metal layer 71g on the plate-like portion 7 side, and the plate-like portion 3 side on the recess 3c. In FIG. 5 and a portion separated from the metal layer 71g on the concave portion 7c on the plate-like portion 7 side. The region facing the recess 3c in the metal layer 51g of the plate-like part 5 is not joined to the metal layer 31g of the plate-like part 3, and the region facing the recess 7c of the metal layer 51g of the plate-like part 5 is The metal layer 71g of the plate-like portion 7 is not joined. The joint surface between the plate-like portion 3 and the plate-like portion 5 is a joint surface between the AuSn solder layer 31d and the AuSn solder layer 51d. The joint surface between the plate-like portion 5 and the plate-like portion 7 is a joint surface between the AuSn solder layer 51d and the AuSn solder layer 71d.

  Each of the copper plate portion 31a and the copper plate portion 71a has a thickness of 0.5 mm or more and 1.5 mm or less, and can have a thickness of, for example, about 0.5 mm. Further, the semiconductor laser element 11 is provided on the surface 1a of the heat sink 1 as described later (see FIGS. 4 and 5), but both the copper plate portion 31a and the copper plate portion 71a have high thermal conductivity. The heat generated from the semiconductor laser element 11 can be efficiently released to the outside. Both the Ni plating layer 31b and the Ni plating layer 71b have a thickness of 1 μm or more, and can have a thickness of about 2 μm, for example. Each of the Ni plating layer 31b and the Ni plating layer 71b is provided as a barrier metal for bonding with a dissimilar metal. Each of the Au plating layer 31c and the Au plating layer 71c has a thickness of 0.2 μm to 2 μm, and can have a thickness of 0.2 μm, for example. Each of the Au plating layer 31c and the Au plating layer 71c is provided as a barrier metal for bonding with a dissimilar metal. The Au plating layer 31c and the Au plating layer 71c are necessary for bonding with the AuSn solder layer 31d and the AuSn solder layer 71d, respectively. Each of the AuSn solder layer 31d and the AuSn solder layer 71d has a thickness of 1 μm or more and 20 μm or less, and can have a thickness of about 5 μm, for example. Both the AuSn solder layer 31d and the AuSn solder layer 71d are used for the purpose of joining with dissimilar metals and for the purpose of preventing corrosion.

  Each of the low thermal expansion coefficient member 331a and the low thermal expansion coefficient member 731a is made of an insulating material, and can be made of, for example, AlN. Each of the low thermal expansion coefficient member 331a and the low thermal expansion coefficient member 731a has a thickness of 0.1 mm to 0.5 mm, and can have a thickness of, for example, about 0.3 mm. Since the heat sink 1 has the low thermal expansion coefficient member 331a and the low thermal expansion coefficient member 731a, the heat sink 1 has an insulating property in the semiconductor laser stack device 101 described later (see FIGS. 4 and 5). Since both the low thermal expansion coefficient member 331a and the low thermal expansion coefficient member 731a have high thermal conductivity, the heat generated from the semiconductor laser element 11 can be efficiently released to the outside. Each of the Ni plating layer 331b and the Ni plating layer 731b has a thickness of 1 μm or more, and can have a thickness of about 2 μm, for example. Each of the Ni plating layer 331b and the Ni plating layer 731b is provided as a barrier metal for bonding with a dissimilar metal. Each of the Au plating layer 331c and the Au plating layer 731c has a thickness of 0.2 μm to 2 μm, and may have a thickness of 0.2 μm, for example. Each of the Au plating layer 331c and the Au plating layer 731c is provided as a barrier metal for bonding with a dissimilar metal. The Au plating layer 331c and the Au plating layer 731c are necessary for bonding with the AuSn solder layer 331d and the AuSn solder layer 731d, respectively. Each of the AuSn solder layer 331d and the AuSn solder layer 731d has a thickness of 1 μm or more and 10 μm or less, and can have a thickness of about 3 μm, for example. The AuSn solder layer 331d and the AuSn solder layer 731d are both used for the purpose of joining with dissimilar metals and for the purpose of preventing corrosion.

  Both the copper plate part 35a and the copper plate part 75a have a thickness of 0.1 mm or more and 0.5 mm or less, and can have a thickness of, for example, about 0.3 mm. Both the copper plate portion 35a and the copper plate portion 75a have high thermal conductivity in order to efficiently release the heat generated from the semiconductor laser element 11 provided on the surface 1a of the heat sink 1 to the outside. Each of the copper plate portion 35a and the copper plate portion 75a serves as a portion for allowing a current to flow in the semiconductor laser stack device 101, the semiconductor laser stack device 102, or the semiconductor laser stack device 103 (see FIGS. 4 to 8) described later. Yes. Both the Ni plating layer 35b and the Ni plating layer 75b have a thickness of 1 μm or more, and can have a thickness of about 2 μm, for example. Each of the Ni plating layer 35b and the Au plating layer 75c is provided as a barrier metal for bonding with a dissimilar metal. Each of the Au plating layer 35c and the Au plating layer 75c has a thickness of 0.2 μm or more and 0.3 μm or less, and can have a thickness of 0.2 μm, for example. Both the Au plating layer 35c and the Au plating layer 75c are provided for bonding with the semiconductor laser element 11 and for corrosion resistance against the outside air. Each of the AuSn solder layer 35d and the AuSn solder layer 75d has a thickness of 1 μm or more and 10 μm or less, and can have a thickness of about 3 μm, for example. Both the AuSn solder layer 35d and the AuSn solder layer 75d are used for the purpose of preventing corrosion.

  The low thermal expansion coefficient member 51a is made of a low thermal expansion material for suppressing the thermal expansion of the heat sink 1 itself, and can be made of, for example, electrically insulating AlN. The low thermal expansion coefficient member 51a can also be made of conductive Mo or W. The low thermal expansion coefficient member 51a has a thickness of 0.1 mm or more and 0.5 mm or less, and can have a thickness of, for example, about 0.1 mm. The Ni plating layer 51b has a thickness of 1 μm or more, and can have a thickness of about 2 μm, for example. The Ni plating layer 51b is provided as a barrier metal for bonding with a dissimilar metal. The Au plating layer 51c is provided as a barrier metal for bonding with a dissimilar metal. The Au plating layer 51c is necessary for bonding with the AuSn solder layer 51d. The AuSn solder layer 51d has a thickness of 1 μm or more and 10 μm or less, and can have a thickness of about 3 μm, for example. The AuSn solder layer 51d is used for the purpose of joining with dissimilar metals and for the purpose of preventing corrosion.

  As described above, in the case of the heat sink 1 according to this embodiment having the plate-like portion 331 and the plate-like portion 731, the surface 1 a and the surface 1 b are electrically insulated. Moreover, since the heat sink 1 includes four copper plates, that is, the copper plate portion 31a, the copper plate portion 35a, the copper plate portion 71a, and the copper plate portion 75a, heat (for example, heat generated from the semiconductor laser element 11 described later) is discharged. It can be done efficiently.

  Next, each of the AuSn solder layer 31d, the AuSn solder layer 331d, the AuSn solder layer 35d, the AuSn solder layer 51d, the AuSn solder layer 71d, the AuSn solder layer 731d, and the AuSn solder layer 75d, and an AuSn solder layer 332d described later. The effect of the AuSn solder layer 732d will be described. AuSn solder serves as a bonding material during lamination, and contains a large amount of Au as a main component so that the interface between different metals can be stabilized. The molten solder surface is a strong Au alloy film, and is resistant to acidity and alkalinity. Defects such as vacancies are reduced, and the surface accuracy is very smooth. By melting and smoothing the surface uniformly, defects are eliminated, local corrosion is prevented, and mechanical damage caused by the coolant flowing in the flow path F is reduced, so the progress of deterioration is suppressed. Therefore, long-term reliability is improved. The composition ratio of the AuSn solder can be Au: Sn = 80: 20 (wt%). The AuSn solder having this composition ratio is a high melting point solder containing Au as a main component, and has a large content of Au and functions as a barrier layer. Moreover, in the case of the composition ratio of 80:20, since it is also a eutectic point of AuSn solder, the solder itself is also stable. The AuSn solder layer has a corrosion resistance function. Note that the roughness of the surface of the AuSn solder layer (the surface after the AuSn solder is melted) is smoother than the Au plating surface (the surface roughness Ra of the Au plating surface was about 0.2 μm, but the AuSn solder) The surface roughness Ra of the surface after melting was about 0.02 μm) and the solubility of the AuSn solder layer (AuSn solder after melting), that is, hydrochloric acid, nitric acid, aqua regia, and further dissolved Au It has already been demonstrated that the solubility of the AuSn solder layer by the potassium iodide that can be made is very low.

  In addition, since the plate-like portion 5 and the plate-like portion 3 and the plate-like portion 5 and the plate-like portion 7 are all bonded via AuSn solder, the bonding surface is not a heterogeneous metal interface, Thus, corrosiveness at the dissimilar metal interface is avoided. Further, the plate-like portion 35 and the plate-like portion 331, the plate-like portion 331 and the plate-like portion 31, the plate-like portion 31 and the plate-like portion 5, the plate-like portion 5 and the plate-like portion 71, the plate-like portion 71 and the plate-like portion. Since all 731 are joined via AuSn solder, the joining surface is not a dissimilar metal interface, and thus corrosiveness at the dissimilar metal interface is avoided.

  Next, an example of a semiconductor laser stack apparatus using the heat sink 1 according to this embodiment will be described with reference to FIGS. 4 and 5. The heat sink 1 shown in FIG.4 and FIG.5 has the low thermal expansion coefficient member 331a and the low thermal expansion coefficient member 731a, and the surface 1a and the surface 1b are electrically insulated. 4 is a perspective view of the semiconductor laser stack apparatus 101, FIG. 5A is a side view of the semiconductor laser stack apparatus 101, and FIG. 5B is a front view of the semiconductor laser stack apparatus 101.

  The semiconductor laser stack apparatus 101 includes three heat sinks 1, two electrically insulating spacers 13, three semiconductor laser elements 11, and conductive lead plates 15a to 15d. The three heat sinks 1 and the two spacers 13 include a heat sink 1 (hereinafter referred to as a first stage heat sink 1), a spacer 13, a heat sink 1 (hereinafter referred to as a second stage heat sink 1), a spacer 13, and a heat sink 1. They are stacked in the order (referred to as the third stage heat sink 1). The thickness of the semiconductor laser element 11 is smaller than the thickness of the spacer 13. A semiconductor laser element 11 is provided on the surface 1 a of the heat sink 1. The semiconductor laser element 11 is in contact with a plate-like portion 35 formed on the surface 1 a of the heat sink 1 where the semiconductor laser element 11 is provided. The semiconductor laser element 11 has a p side surface serving as a p terminal and an n side surface opposite to the p side surface and serving as an n terminal. The p side surface of the semiconductor laser element 11 is in contact with the surface 1a (the plate-like portion 35).

  In addition, a lead plate 15a to a lead plate 15c are provided on each of the surfaces 1a of the first to third heat sinks 1. A lead plate 15 d is provided on the n side surface of the semiconductor laser element 11 provided on the surface 1 a of the third stage heat sink 1.

  The lead plate 15a is in contact with the surface 1a (ie, the plate-like portion 35) of the first stage heat sink 1, and the lead plate 15b is in contact with the surface 1a (ie, the plate-like portion 35) of the second stage heat sink 1. The lead plate 15c is in contact with the surface 1a (ie, the plate-like portion 35) of the third stage heat sink 1, and the lead plate 15d is n of the semiconductor laser element 11 provided on the surface 1a of the third stage heat sink 1. Touching the side. The lead plate 15 a is electrically connected to the p terminal of the semiconductor laser element 11 provided on the surface 1 a of the first stage heat sink 1 via the plate-like portion 35 of the first stage heat sink 1. . The lead plate 15 b is electrically connected to the p terminal of the semiconductor laser element 11 provided on the surface 1 a of the second stage heat sink 1 via the plate-like portion 35 of the second stage heat sink 1. . The lead plate 15 c is electrically connected to the p terminal of the semiconductor laser element 11 provided on the surface 1 a of the third stage heat sink 1 via the plate-like portion 35 of the third stage heat sink 1. . The lead plate 15 d is electrically connected to the n terminal of the semiconductor laser element 11 provided on the surface 1 a of the third stage heat sink 1.

  The lead plate 15b is also in contact with the n side surface of the semiconductor laser element 11 provided on the surface 1a of the first stage heat sink 1, and the lead plate 15c is provided on the surface 1a of the second stage heat sink 1. The n side surface of the semiconductor laser element 11 thus formed is also in contact. The lead plate 15b electrically connects the n terminal of the semiconductor laser element 11 provided on the surface 1a of the first stage heat sink 1 and the plate-like portion 35 provided on the surface 1a of the second stage heat sink 1. Connect to. The lead plate 15c electrically connects the n terminal of the semiconductor laser element 11 provided on the surface 1a of the second stage heat sink 1 and the plate-like portion 35 provided on the surface 1a of the third stage heat sink 1. Connect to.

  The n terminal of the semiconductor laser element 11 provided on the surface 1a of the first stage heat sink 1 is connected via a lead plate 15b and a plate-like portion 35 provided on the surface 1a of the second stage heat sink 1. The second stage heat sink 1 is electrically connected to the p terminal of the semiconductor laser element 11 provided on the surface 1a of the heat sink 1. The n terminal of the semiconductor laser element 11 provided on the surface 1a of the second-stage heat sink 1 is connected via a lead plate 15c and a plate-like portion 35 provided on the surface 1a of the third-stage heat sink 1. The third stage heat sink 1 is electrically connected to the p terminal of the semiconductor laser element 11 provided on the surface 1a.

  The semiconductor laser stack apparatus 101 having the configuration described above includes three heat sinks 1, each of which is separated by a spacer 13, and a space is formed between adjacent heat sinks 1. The semiconductor laser element 11 provided in each heat sink 1 can be accommodated in this space. Since the thickness of the semiconductor laser element 11 is smaller than the thickness of the spacer 13, the semiconductor laser element 11 can avoid pressing of the adjacent heat sink 1.

  In addition, although the surface 1a and the surface 1b of the heat sink 1 are electrically insulated, the three semiconductor laser elements 11 provided on each of the three heat sinks 1 by the lead plate 15b and the lead plate 15c, Electrically connected in series. This will be specifically described. The p-terminal of the semiconductor laser element 11 provided on the surface 1a of the first stage heat sink 1 is electrically connected to the lead plate 15a and the plate-like portion 35 of the first stage heat sink 1, and the first terminal The n terminal of the semiconductor laser element 11 provided on the surface 1a of the stage heat sink 1 is connected to the second stage heat sink 1 via the lead plate 15b and the plate-like portion 35 of the second stage heat sink 1. It is electrically connected to the p terminal of the semiconductor laser element 11 provided on the surface 1a. The n terminal of the semiconductor laser element 11 provided on the surface 1a of the second-stage heat sink 1 is connected to the third-stage heat sink 1 via the lead plate 15c and the plate-like portion 35 of the third-stage heat sink 1. It is connected to the p terminal of the semiconductor laser element 11 provided on the surface 1 a of the heat sink 1.

  The plate-like portion 31, plate-like portion 5 and plate-like portion 71 constituting the flow path F including the recess 3c, the through hole 5c and the recess 7c are composed of a low thermal expansion coefficient member 331a and a low thermal expansion coefficient made of an insulating material. Since the member 731a is electrically insulated from the plate-like portion 35 and the plate-like portion 75 to which a voltage is applied via the lead plate 15a to the lead plate 15c, the cooling flowing in the flow path F is performed. The possibility of current flowing through the liquid is low. Therefore, as the coolant flowing in the flow path F, it is possible to use a liquid such as tap water whose conductivity is not defined at least.

(Modification)
In addition, although the plate-like part 3 has the plate-like part 331 and the plate-like part 7 has the plate-like part 731, the plate-like part 3 is replaced with the plate-like part 331. The plate-like portion 332 shown in FIG. 3A may be included, or the plate-like portion 7 may have the plate-like portion 732 shown in FIG. Good. The plate-like portion 332 and the plate-like portion 732 have the same configuration. When the plate-like portion 3 has a plate-like portion 332 instead of the plate-like portion 331 and the plate-like portion 7 has a plate-like portion 732 instead of the plate-like portion 731, the flow path F ( As the coolant flowing through the water supply channel 9a, the recess 7c, the through hole 5c, the recess 3c, and the drainage channel 9b), a liquid with low conductivity is used. The heat sink 1 is described as a heat sink 21 in the present modification, the plate-shaped portion 3 is described as a plate-shaped portion 23 in the present modification, and the plate-shaped portion 7 is a plate-shaped in the present modification. Part 27 (see FIGS. 1 and 2).

  Next, the configuration of the plate-like portion 332 will be described with reference to FIG. The plate-like portion 332 includes a low thermal expansion coefficient member 332a and a metal layer 332g (Ni plating layer 332b, Au plating layer 332c, and AuSn solder layer 332d) that covers the low thermal expansion coefficient member 332a. The Ni plating layer 332b, the Au plating layer 332c, and the AuSn solder layer 332d are sequentially stacked on the surface of the low thermal expansion coefficient member 332a (including the end surface 332e of the low thermal expansion coefficient member 332a). The plate-like part 332 is provided on the copper plate part 31 a via the metal layer 31 g of the plate-like part 31. The Ni plating layer 332b covers the surface of the low thermal expansion coefficient member 332a (including the end surface 332e of the low thermal expansion coefficient member 332a) without exposing it, and the Au plating layer 332c does not expose the surface of the Ni plating layer 332b. The AuSn solder layer 332d covers the surface of the Au plating layer 332c without exposing it. The end surface 332e includes a surface of the low thermal expansion coefficient member 332a on the outer wall surface side of the plate-shaped portion 332, a surface of the low thermal expansion coefficient member 332a on the inner wall surface side of the water supply channel 9a (through hole 3a), and a drainage channel 9b ( This corresponds to the surface of the low thermal expansion coefficient member 332a on the inner wall surface side of the through hole 3b). The metal layer 332g is also provided on the end surface 332e. The AuSn solder layer 332d is provided on the surface of the metal layer 332g. A portion of the metal layer 332g provided on the end surface 332e constitutes a part of the outer wall surface of the heat sink 1, a part of the inner wall surface of the water supply channel 9a, and a part of the inner wall surface of the water supply channel 9b.

  A configuration of the plate-like portion 732 will be described with reference to FIG. The plate-like portion 732 includes a low thermal expansion coefficient member 732a and a metal layer 732g (Ni plating layer 732b, Au plating layer 732c, and AuSn solder layer 732d) that covers the low thermal expansion coefficient member 732a. The Ni plating layer 732b, the Au plating layer 732c, and the AuSn solder layer 732d are sequentially stacked on the surface of the low thermal expansion coefficient member 732a (including the end surface 732e of the low thermal expansion coefficient member 732a). The plate-like part 732 is provided on the copper plate part 71 a via the metal layer 71 g of the plate-like part 71. The Ni plating layer 732b covers the surface of the low thermal expansion coefficient member 732a (including the end surface 732e of the low thermal expansion coefficient member 732a) without exposing it, and the Au plating layer 732c does not expose the surface of the Ni plating layer 732b. The AuSn solder layer 732d covers the surface of the Au plating layer 732c without exposing it. The end surface 732e includes a surface of the low thermal expansion coefficient member 732a on the outer wall surface side of the plate-like portion 732, a surface of the low thermal expansion coefficient member 732a on the inner wall surface side of the water supply channel 9a (through hole 7a), and a drainage channel 9b ( This corresponds to the surface of the low thermal expansion coefficient member 732a on the inner wall surface side of the through hole 7b). The metal layer 732g is also provided on the end face 732e. The AuSn solder layer 732d is provided on the surface of the metal layer 732g. A portion of the metal layer 732g provided on the end surface 732e constitutes a part of the outer wall surface of the heat sink 1, a part of the inner wall surface of the water supply channel 9a, and a part of the inner wall surface of the water supply channel 9b.

  Both the low thermal expansion coefficient member 332a and the low thermal expansion coefficient member 732a can be made of, for example, conductive Mo or W. Each of the low thermal expansion coefficient member 332a and the low thermal expansion coefficient member 732a has a thickness of 0.1 mm to 0.5 mm, and can have a thickness of, for example, about 0.3 mm. By configuring the heat sink including the low thermal expansion coefficient member 332a and the low thermal expansion coefficient member 732a, the stress load on the semiconductor laser element 11 can be reduced, and the surface of the low expansion coefficient member is made of a material having high thermal conductivity. By covering, heat generated from the semiconductor laser element 11 can be efficiently released to the outside. Both the Ni plating layer 332b and the Ni plating layer 732b have a thickness of 1 μm or more, and can have a thickness of about 2 μm, for example. Both the Ni plating layer 332b and the Ni plating layer 732b are provided as barrier metals for bonding with different metals. Each of the Au plating layer 332c and the Au plating layer 732c has a thickness of 0.2 μm or more and 2 μm or less, and can have a thickness of 0.2 μm, for example. Each of the Au plating layer 332c and the Au plating layer 732c is provided as a barrier metal for bonding with a dissimilar metal. The Au plating layer 332c and the Au plating layer 732c are necessary for bonding with the AuSn solder layer 332d and the AuSn solder layer 732d, respectively. Each of the AuSn solder layer 332d and the AuSn solder layer 732d has a thickness of 1 μm or more and 10 μm or less, and can have a thickness of about 3 μm, for example. The AuSn solder layer 332d and the AuSn solder layer 732d are both used for the purpose of joining with dissimilar metals and for the purpose of preventing corrosion. The low thermal expansion coefficient member 51a can be made of conductive Mo or W.

As described above, in the case of the heat sink 21 according to this modification having the plate-like portion 332 and the plate-like portion 732, the surface 1a and the surface 1b are electrically connected.
Note that the heat sink 21 according to this modification may not have the plate-like portion 332, the plate-like portion 35, the plate-like portion 732, and the plate-like portion 75. That is, the heat sink 21 according to this modification may be configured by only the plate-like portion 31, the plate-like portion 5, and the plate-like portion 71. If the low thermal expansion coefficient member 51a of the plate-like portion 5 is provided, the stress load on the semiconductor laser element 11 can be reduced, and the distance between the semiconductor laser element 11 and the flow path F becomes shorter and flows through the flow path F. The cooling effect by the coolant is greater.

  Next, two examples of the semiconductor laser stack apparatus using the heat sink 21 according to the modification will be described with reference to FIGS. The heat sink 21 shown in FIGS. 6 to 8 includes a low thermal expansion coefficient member 332a and a low thermal expansion coefficient member 732a, and the surface 1a and the surface 1b are electrically connected. First, the configuration of the semiconductor laser stack device 102 using the heat sink 21 according to the modification will be described with reference to FIGS. 6 is a perspective view of the semiconductor laser stack apparatus 102, and FIG. 7 is a side view of the semiconductor laser stack apparatus 102.

  The semiconductor laser stack device 102 includes three heat sinks 21, two electrically insulating spacers 13, three semiconductor laser elements 11, a conductive lead plate 15a, and a lead plate 15d. The three heat sinks 21 and the two spacers 13 include a heat sink 21 (hereinafter referred to as a first stage heat sink 21), a spacer 13, a heat sink 21 (hereinafter referred to as a second stage heat sink 21), a spacer 13, and a heat sink 21. They are stacked in the order (referred to as the third stage heat sink 21). The semiconductor laser element 11 and the spacer 13 mounted on the semiconductor laser stack apparatus 102 have the same thickness. The lead plate 15a is provided on the surface 1b of the first stage heat sink 21 and is in contact with the surface 1b. The lead plate 15d is provided on the n side surface of the semiconductor laser element 11 provided on the surface 1a of the third stage heat sink 21, and is in contact with the n side surface.

  The semiconductor laser element 11 and the spacer 13 provided between the first-stage heat sink 21 and the second-stage heat sink 21 both include the surface 1a of the first-stage heat sink 21 and the second-stage heat sink 21. The heat sink 21 is in contact with the surface 1b of the heat sink 21. The p-side surface of the semiconductor laser element 11 provided between the first stage heat sink 21 and the second stage heat sink 21 is in contact with the surface 1 a of the first stage heat sink 21. The n side surface is in contact with the surface 1b of the second stage heat sink 21. The p terminal of the semiconductor laser element 11 provided on the surface 1a of the first stage heat sink 21 is electrically connected to the first stage heat sink 21 and the lead plate 15a. The n terminal of the semiconductor laser element 11 provided on the surface 1 a of the first stage heat sink 21 is electrically connected to the second stage heat sink 21.

  The semiconductor laser element 11 and the spacer 13 provided between the second-stage heat sink 21 and the third-stage heat sink 21 both have the surface 1a of the second-stage heat sink 21 and the third-stage heat sink 21. The heat sink 21 is in contact with the surface 1b of the heat sink 21. The p-side surface of the semiconductor laser element 11 provided between the second-stage heat sink 21 and the third-stage heat sink 21 is in contact with the surface 1a of the second-stage heat sink 21. The n side surface is in contact with the surface 1b of the third stage heat sink 21. The p terminal of the semiconductor laser element 11 provided on the surface 1a of the second stage heat sink 21 is connected to the second stage heat sink 21 and the semiconductor laser element 11 provided on the surface 1a of the first stage heat sink 21. It is electrically connected to the n terminal. The n terminal of the semiconductor laser element 11 provided on the surface 1 a of the second stage heat sink 21 is electrically connected to the third stage heat sink 21.

  The p-side surface of the semiconductor laser element 11 provided on the surface 1a of the third stage heat sink 21 is in contact with the surface 1a. The p terminal of the semiconductor laser element 11 provided on the surface 1a of the third stage heat sink 21 is connected to the p-terminal of the semiconductor laser element 11 provided on the surface 1a of the third stage heat sink 21 and the second stage heat sink 21. It is electrically connected to the n terminal. The n terminal of the semiconductor laser element 11 provided on the surface 1a of the third stage heat sink 21 is electrically connected to the lead plate 15d.

  In the semiconductor laser stack apparatus 102 having the above-described configuration, the heat sink 21 is conductive, that is, the surface 1a and the surface 1b of the heat sink 21 are electrically connected, so that the p side surface of the semiconductor laser element 11 is By directly bonding the heat sink 21 to each of the n side surfaces, the plurality of semiconductor laser elements 11 mounted on the semiconductor laser stack device 102 can be electrically connected in series. In addition, since the heat sink 21 has conductivity, a coolant having a low conductivity can be used as the coolant flowing in the heat sink 21 so that current does not leak from the heat sink 21.

  Next, the configuration of the semiconductor laser stack apparatus 103 using the heat sink 21 according to the modification will be described with reference to FIG. FIG. 8 is a side view of the semiconductor laser stack device 103. The semiconductor laser stack device 103 includes three heat sinks 21, three spacers 17, and three semiconductor laser elements 11. The spacer 17 includes a spacer 17a, a spacer 17a, and a spacer 17c. The spacer 17a, the spacer 17b, and the spacer 17c are stacked on the surface 1a of the heat sink 21 in this order. The three heat sinks 21 and the three spacers 17 are a heat sink 21 (hereinafter referred to as a first stage heat sink 21), a spacer 17a, a spacer 17b, a spacer 17c, and a heat sink 21 (hereinafter referred to as a second stage heat sink 21). , Spacer 17a, spacer 17b, spacer 17c, heat sink 21 (referred to as third-stage heat sink 21), spacer 17a, spacer 17b, and spacer 17c.

  The surface 1a of the first-stage heat sink 21 is in contact with the p-side surface of the semiconductor laser element 11 provided on the surface 1a. Therefore, the first-stage heat sink 21 is provided on the surface 1a. 11 is electrically connected to the p terminal. The surface 1a of the second-stage heat sink 21 is in contact with the p-side surface of the semiconductor laser element 11 provided on the surface 1a. Accordingly, the second-stage heat sink 21 is provided on the surface 1a. 11 is electrically connected to the p terminal. The surface 1a of the third-stage heat sink 21 is in contact with the p-side surface of the semiconductor laser element 11 provided on the surface 1a. Therefore, the third-stage heat sink 21 is provided with the semiconductor laser element provided on the surface 1a. 11 is electrically connected to the p terminal.

  The spacer 17a is made of an electrically insulating material, and both the spacer 17b and the spacer 17c are made of a conductive material. The spacer 17b and the spacer 17c may be made of the same material, or may be made of different materials. Further, the spacer 17b and the spacer 17c may be integrally formed, or may be formed separately and joined to each other. The spacer 17b has a protrusion 17d that protrudes closer to the semiconductor laser element 11 than the spacer 17c. The n terminals of the semiconductor laser elements 11 provided on the respective surfaces 1 a of the first to third heat sinks 21 are connected to the spacers 17 provided on the same surface 1 a as the semiconductor laser elements 11 via the metal wires 19. Is electrically connected to the surface of the protruding portion 17d of the spacer 17b.

  The semiconductor laser stack apparatus 103 having the configuration described above includes three heat sinks 1, each of which is separated by a spacer 17, and a space is formed between adjacent heat sinks 1. The semiconductor laser element 11 provided in each heat sink 1 can be accommodated in this space. Since the thickness of the semiconductor laser element 11 is smaller than the thickness of the spacer 17, the semiconductor laser element 11 can avoid pressing the adjacent heat sink 1. The n terminal of the semiconductor laser element 11 is electrically connected to the p terminal of the adjacent semiconductor laser element 11 through the metal wire 19, the spacer 17b, the spacer 17, and the heat sink 21. For example, the n terminal of the semiconductor laser element 11 provided on the surface 1a of the first-stage heat sink 21 has a metal wire 19 between the first-stage heat sink 21 and the second-stage heat sink 21; Provided on the surface 1a of the second stage heat sink 21 via the spacer 17b and spacer 17c of the spacer 17 provided on the surface 1a of the first stage heat sink 21 and the second stage heat sink 21. The semiconductor laser element 11 is electrically connected to the p terminal. Accordingly, a plurality of semiconductor laser elements 11 mounted on the semiconductor laser stack device 103 are electrically connected in series with a simple configuration using the metal wires 19.

  DESCRIPTION OF SYMBOLS 1,21 ... Heat sink, 101, 102, 103 ... Semiconductor laser stack apparatus, 11 ... Semiconductor laser element, 13, 17, 17a, 17b, 17c ... Spacer, 15a, 15b, 15c, 15d ... Lead plate, 17d ... Projection 19 ... Metal wire, 1a, 1b, 5d, 5e ... Surface, 23, 27, 3, 31, 331, 332, 35, 5, 7, 71, 731, 732, 75 ... Plate-like part, 31a, 35a, 71a, 75a ... copper plate part, 31b, 331b, 332b, 732b, 35b, 51b, 71b, 731b, 75b ... Ni plating layer, 31c, 331c, 332c, 35c, 51c, 71c, 731c, 732c, 75c ... Au plating layer , 31d, 331d, 332d, 35d, 51d, 71d, 731d, 75d, 732d ... AuSn solder layer, 3 e, 331e, 332e, 35e, 35f, 51e, 71e, 731e, 732e, 75e, 75f ... end face, 31g, 331g, 332g, 332g, 35g, 51g, 71g, 731g, 732g, 75g ... metal layer, 331a, 332a, 51a , 731a, 732a ... low thermal expansion coefficient member, 3a, 3b, 5a, 5b, 5c, 7a, 7b ... through-hole, 3c, 7c ... recess, 3d, 7d ... main surface, 3e, 7e ... back surface, 3f, 7f ... Opening part, 9a ... water supply channel, 9b ... drainage channel, AX1, AX2 ... central axis, F ... channel.

Claims (3)

A heat sink for cooling a semiconductor element,
A first plate-like portion having a plate-like first member and a first metal layer covering the first member;
A second plate-shaped portion having a first copper plate portion and a second metal layer covering the first copper plate portion;
A third plate having a second copper plate and a third metal layer covering the second copper plate,
The third plate-like portion, the first plate-like portion , and the second plate-like portion are laminated in order,
The second plate-like portion has a first recess provided on a main surface on the first plate-like portion side,
The third plate-like portion has a second recess provided on the main surface on the first plate-like portion side,
The first plate-like portion has a through hole communicating with the first concave portion and the second concave portion,
The first metal layer has a first Ni plating layer, a first Au plating layer, and a first AuSn solder layer,
The first Ni plating layer, the first Au plating layer, and the first AuSn solder layer are sequentially laminated on the member of the first member,
The second metal layer has a second Ni plating layer, a second Au plating layer, and a second AuSn solder layer,
The second Ni plating layer, the second Au plating layer, and the second AuSn solder layer are sequentially laminated on the first copper plate portion.
The third metal layer has a third Ni plating layer, a third Au plating layer, and a third AuSn solder layer,
The third Ni plating layer, the third Au plating layer, and the third AuSn solder layer are sequentially stacked on the second copper plate portion,
The first metal layer is bonded to the second metal layer on the second plate-like portion side and to the third metal layer on the third plate-like portion side. A portion that is on the second plate-like portion side and is separated from the second metal layer on the first recess, and that is on the third plate-like portion side and the second plate portion side. And a portion spaced from the third metal layer on the concave portion of
The joint surface between the first plate-like portion and the second plate-like portion is a joint surface between the first AuSn solder layer and the second AuSn solder layer,
The joint surface between the first plate-like portion and the third plate-like portion is a joint surface between the first AuSn solder layer and the third AuSn solder layer,
The material of the first member is any one of AlN, Mo, and W.
A heat sink characterized by that. The second plate-like portion further includes a plate-like second member, a third copper plate portion, and a fourth metal layer covering the third copper plate portion,
The third plate-like portion further includes a plate-like third member, a fourth copper plate portion, and a fifth metal layer covering the fourth copper plate portion,
The second member is provided on the first copper plate part via the second metal layer,
The third copper plate portion is provided on the second member via the fourth metal layer,
The third member is provided on the second copper plate portion via the third metal layer,
The fourth copper plate portion is provided on the third member via the fifth metal layer,
The material of the second member and the material of the third member are either AlN, Mo, or W.
The heat sink according to claim 1. The fourth metal layer includes a fourth Ni plating layer and a fourth Au plating layer,
The fifth metal layer includes a fifth Ni plating layer and a fifth Au plating layer,
A heat sink according to claim 2.

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