CHARACTERISTICS OF LPCVD WISI2/N-SI SCHOTTKY CONTACTS

Detailed current-voltage and capacitance-voltage characteristics of LPCVD WSi2/n-Si Schottky contacts are reported in the temperature range of 21 to 170-degrees-C. Diode ideality factor n was found to decrease from a value of 1.46 to 1.15 as temperature is increased. Schottky barrier height phi-B, on the other hand, was found to increase from 0.72 to 0.86 V with temperature. These results suggest that diode characteristics are affected by surface and bulk effects especially at lower temperatures. High-resolution TEM and X-ray photoelectron spectroscopy analyses revealed isolated regions of oxynitride at the silicide/silicon interface that are predominantly located where silicide grain boundaries intersect silicon surface.