Characteristics of LPCVD WSi2/n-Si Schottky contacts

Detailed current-voltage and capacitance-voltage characteristics of low-pressure chemical vapor deposited (LPCVD) WSi₂/n-Si Schottky contacts are reported in the temperature range of 21 to 170°C. The diode ideality factor n was found to decrease from a value of 1.46 to 1.15 as temperature was increased. Schottky barrier height φ_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 transmission electron microscopy (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 the silicon surface