Gold metallization process

摘要

A one step metallization is disclosed for applying a layer of gold or gold alloy to the back of a silicon substrate to facilitate bonding that substrate to a metallized package member. The gold is applied to the substrate, for example by evaporation, while the substrate is maintained at a temperature between about 200 DEG C. and about 360 DEG C. Following the deposition the substrate is quickly cooled to room temperature. The thickness of the gold layer and the deposition temperature are adjusted to insure that the silicon diffusion profile is contained within the gold film during deposition. This insures good adhesion of the gold to the silicon substrate and provides a pure gold surface layer necessary for optimum bonding of the semiconductor substrate to a metallized package portion.