Interfacial reactions of platinum thin films on (111) and (001) germanium

Abstract
A combined plan‐view and cross‐sectional transmission electron microscope study has been carried out to investigate the interfacial reactions in platinum thin films on germanium. Pt2Ge, PtGe, Pt2Ge3, and PtGe2 were found to form at 160, 250, 350, and 400 °C, respectively. Definite orientation relationships were observed between those of Pt2Ge, PtGe, and PtGe2 and (111)Ge. No epitaxial growth of platinum germanides on (001)Ge was observed. The results were found to be partially different from those obtained in a previous investigation. The discrepancy is attributed to different substrate cleaning schemes prior to the metal film depositions in the two studies. It appears that the growth of platinum germanide epitaxy on (111)Ge is not directly correlated with the lattice matches at germanide/Ge interfaces at room temperature.