An x-ray photoelectron spectroscopy/Auger electron spectroscopy study of titanium–palladium thin films on silicon(111)

Abstract

Thin films of palladium (30 Å) on titanium (4–12 Å) were evaporated on silicon at 250 °C in a standard electron beam evaporator. Auger elemental depth profiling and angle resolved x-ray photoelectron spectroscopy show that titanium inverts position with the palladium layer in the deposit. The titanium-rich surface of the deposit consists mostly of titanium oxide. At the surface of the deposit, two components are observed in the Ti 2p spectrum: a high binding energy peak which is due to oxide and a low binding energy peak which is likely due to titanium silicides. Under the titanium-rich region, palladium, in its inverted position, forms a silicide as determined from the palladium 3d and silicon 2p core-level peak positions at the surface. The film configuration and existence of palladium silicide is confirmed by analytical transmission electron microscopy of cross sections of various titanium film thicknesses.