Development of direct bonded aluminum substrates with sintered Ag layer for SiC power modules

Inhalt:
Recently, Ag die-bonding techniques using nano-Ag paste have been studied for use in SiC power modules. Currently, Ag plating is considerably expensive. Thus, we investigated a sintered Ag layer deposited onto DBA substrates using Ag paste containing glass frit as an alternative to plating. Preliminary tests revealed that the behavior of the glass frit is critical to obtaining good adhesion. Adhesion tests were performed to optimize the Ag paste composition. The samples did not fracture after severe thermal cycling tests. Therefore, this new technology is useful for SiC power modules, which are operated at high temperatures.