Heat sink and method for its production
View Patent ↗The present invention provides a liquid-cooling type heat sink which has a high pressure-resistibility and is resistible against the corrosion or erosion-corrosion or electrolytic etching, and a method for its production. The heat sink of the present invention comprises plural base members 21, 31 and 41, the base member being each in plate or block-shape, the base member each having paths 60 shaped on one or both sides of surfaces thereof, and the base members being bonded to each other, wherein a communicating flow path 60 a including path 60, through holes 61, 62, and 63, is formed for a cooling medium to flow in and out. The base members are bonded to each other with a solder layer 54 made of Au—Sn alloy or Sn, while a coating layer of Au 53 is formed on each of the inner surfaces of the bonded base members. At the time of making a bond between the base members, the coating layer of Au 53 and the solder layer 54 are diffused to each other, resulting in formation of a bond layer of alloy 55 containing at least 91 wt % of Au and at most 9 wt % of Sn.
1. A heat sink for cooling a semiconductor device, comprising:
plural base members, the base member being each in plate or block-shape, the base member each having paths shaped on one or both sides of surfaces thereof, and the base members being bonded to each other;
a coating layer of Au being onto the members; and
a bond layer of alloy containing at least 91 wt % of Au and at most 9 wt % of Sn, the bond layer being interposed between connecting regions at which a pair of the base members is bonded,
wherein the paths shaped on surfaces of the base members are connected to each other to form a communicating flow path for a cooling medium inside the bonded base members.
2. The heat sink according to claim 1 , wherein the base members are made of at least one material selected from the group consisting of Cu, Cu—W type alloy, Mo, Fe—Ni—Co type alloy, aluminum nitride and silicon carbide.
3. The heat sink according to claim 1 , further comprising a semiconductor device, wherein the semiconductor device is one selected from the group consisting of a single laser emitter, a laser diode array having plural laser emitters aligned in an array form, various types of transistors, and an integrated circuit.
4. The heat sink according to claim 1 , further comprising a coating layer of Ni being onto the base members, the coating layer of Ni being overlaid with the coating layer of Au.