Wolfspeed, Inc.
Contact and die attach metallization for silicon carbide based devices and related methods of sputtering eutectic alloys

Abstract:

A semiconductor device package includes a package substrate having a die attach region, a silicon carbide (SiC) substrate having a first surface including a semiconductor device layer thereon and a second surface that is opposite the first surface, and a die attach metal stack. The die attach metal stack includes a sputtered die attach material layer that attaches the second surface of the SiC substrate to the die attach region of the package substrate, where the sputtered die attach material layer comprises a void percent of about 15% or less. The sputtered die attach material layer may be formed using a sputter gas including at least one of krypton (Kr), xenon (Xe), or radon (Rn). The die attach metal stack may further include a metal interlayer that prevent contacts with a first barrier metal layer during a phase transition of the die attach material layer.