Effect of thin titanium interfacial layers on the formation of palladium silicide on silicon

Thin titanium and palladium were deposited on (100) and (111) silicon at 250 °C by an electron beam in a vacuum of 10−6 to 10−7 Torr. Analysis by transmission electron microscopy, x‐ray photoelectron spectroscopy, Auger, and Rutherford backscattering spectroscopy showed that, in the range of titanium thicknesses from 2 to 11 A, heteroepitaxial Pd2Si was formed with the TiOx moving to the surface. We propose that the Ti, which has a high heat of formation for the oxide, scavenges oxygen and water from the Si–SiOx surface promoting the formation of a uniform layer of heteroepitaxial Pd2Si grains.