Investigation of Titanium Silicide Formation Using Secondary Ion Mass Spectrometry

ABSTRACTSecondary ion mass spectrometry (SIMS) and X-ray photoelectron spectroscopy (XPS) are used to investigate Ti silicide formation mechanisms on a series of Ti on Si thin films annealed in ultrahigh vacuum (UHV) at different temperatures and durations. The competition between oxygen diffusion and the silicide formation reaction (the socalled “snowplough” effect) is observed directly, as well as a Ti-Si-O layer. The results from these controlled experiments are compared with those from Ti silicide films formed under rapid thermal annealing (RTA) conditions in a production furnace, with and without a TiW barrier layer.