Use of Si KLL Auger shifts and the Auger parameter in XPS to distinguish Ti silicides from a Ti/Si mixture in thin films

Abstract A particular wafer processing step involves deposition of a Ti thin film (˜6 nm to ˜13 nm) on Si, under processing conditions intended to form a silicidewith specific electrical properties. It is difficult, however, to distinguish silicideformation from mere elemental inter-diffusion. Routine laboratory XPS, using an Al X-Ray source(1486.6ev), does have an appropriate probing depth for the film stack involved, but the chemical shifts in Ti (2p) and Si(2p) are too small (