Formation of PtSi Using Polycrystalline Si and Different Annealing Sequences

Abstract

ABSTRACTFormation of PtSi on As-doped polycrystalline Si is studied using different annealing sequences. An incomplete reaction between the Pt and Si is observed using a one-temperature anneal at 550 ° C, with unreacted Pt remaining in the film which is undesirable for the device processing. Using a three-temperature annealing sequence at 200–300–550 ° C in a N2-H2 mixture, a complete reaction is observed between Pt and Si, with no unreacted Pt detected. The results are similar to that using single crystal Si, except for the less-oriented PtSi formed. The three-temperature annealing process described has thus been shown useful to the fabrication of PtSi contacts at device areas containing either single crystalline or polycrystalline Si.