The present invention relates to a method for forming self-aligned metal
silicide contacts over at least two silicon-containing semiconductor
regions that are spaced apart from each other by an exposed dielectric
region. Preferably, each of the self-aligned metal silicide contacts so
formed comprises at least nickel silicide and platinum silicide with a
substantially smooth surface, and the exposed dielectric region is
essentially free of metal and metal silicide. More preferably, the method
comprises the steps of nickel or nickel alloy deposition, low-temperature
annealing, nickel etching, high-temperature annealing, and aqua regia
etching.