Heat sink and laser diode

Abstract

The present invention is directed to improve reliability by preventing deterioration in the structure of an inner wall of a water channel caused by galvanic corrosion. A heat sink in which a water channel of a cooling fluid is formed by stacking and bonding a plurality of thin plates, in which a surface in the water channel is made of the same metal material except for at least an end of a bonded part of the thin plates.

1 . A heat sink in which a water channel of a cooling fluid is formed by stacking and bonding a plurality of thin plates, wherein a surface in the water channel is made of the same metal material except for at least an end of a bonded part of the thin plates. 
     
     
         2 . The heat sink according to  claim 1 , wherein the plurality of thin plates are bonded with an insert metal in between. 
     
     
         3 . The heat sink according to  claim 2 , wherein:
 all of the plurality of thin plates are made of a single metal material, the thin plates are bonded to each other with the insert metal in between, and   the surface of each of the thin plates is exposed in the surface except for an end of the bonded part in the water channel.   
     
     
         4 . The heat sink according to  claim 2 , wherein the insert metal is exposed including an end of the bonded part in the surface in the water channel. 
     
     
         5 . The heat sink according to  claim 2 , wherein the thin plates are bonded by solid-phase diffusion bonding.