Method of soldering semiconductor substrate on supporting plate

Abstract From the Canadian patent

In order to solder a silicon substrate on a supporting plate, an aluminum thin plate is inserted therebetween as a solder metal layer. An assembly thus obtained is heated to 580°C which is higher than the recrystallization temperature 264°C of the aluminum thin plate but is lower than the eutectic reaction temperature 585°C of the interface between the silicon substrate and the aluminum thin plate. After the assembly is held at 580°C for twenty minutes, the assembly is further heated to 610°C in order to melt the aluminum thin plate into which silicon atoms are diffused. The aluminum thin plate changes uniformly to an eutectic layer consisting of silicon and aluminum, whereby the silicon …