Implant enhancement of titanium silicidation

摘要

A method of forming silicided narrow (i.e., sub-0.25 mu m) polysilicon lines. A layer of titanium is deposited over a semiconductor body having polysilicon lines formed thereon Either before or after the titanium deposition and before the react step, an implant is performed using a gas that will not poison the subsequent silicidation reaction. Exemplary gases include the noble element gases such as argon, krypton, xenon, and neon. The titanium is then reacted with the polysilicon lines to form titanium silicide. The gas implant causes the C49 grain size of the titanium silicide to be reduced, which makes the transformation to the C54 phase easier. Finally, an anneal is performed to transform the titanium silicide from the C49 phase to the C54 phase.