Thermal stability enhancement of silicides by using N2 and Ar implantation

Thermal stability of titanium and cobalt silicides were enhanced by implementing nitrogen or argon implantation prior to silicide formation. Silicide formed on N2 or Ar implanted blanket wafers, P-type, or N-type poly-silicon had better thermal stability as compared with non-implant ones. Furthermore, Ar implanted approach demonstrated superior thermal stability characteristics even in a RTP test of 1000 °C/180 s. With the aid of N2 or Ar implantation, the grain growth of the silicide under high temperature was suppressed and thus it prohibited further diffusion and redistribution of the metal.