Patent ID: 6331486
Filing Date: 2001-12-18
Classification: H01L

Abstract:
A method for reducing the contact resistance of metal silicide contacts comprising the steps of:(a) forming a metal germanium alloy layer over a silicon-containing substrate, wherein said metal is Co, Ti, Ni or mixtures thereof;(b) annealing said metal germanium alloy layer at a temperature sufficient to convert at least a portion of said metal germanium alloy layer into a metal silicide layer that is substantially non-etchable compared to the unreacted metal germanium alloy layer, while forming a Si--Ge interlayer between said silicon-containing substrate and said substantially non-etchable metal silicide layer;(c) removing any remaining metal germanium alloy layer, with the proviso that when Ti or Co are employed a second annealing step follows step (c) that is capable of converting the substantially non-etchable Ti or Co silicide phase into Co disilicide or C54 phase of TiSi.sub.2.