Interfaces characteristics between tungsten silicide electrodes and thin dielectrics

Abstract In today’s ULSI technology there is an increasing demand in metal electrodes for storage capacitors and transistors. In this publication we present an investigation of MOS capacitor structures with CVD tungsten silicide (WSi x ) as metal electrode in conjunction with silicon dioxide (SiO 2 ) and oxidized nitride (NO). Bulk silicon and poly silicon were used as second electrode, respectively. Tungsten silicide has been used both as gate electrode and as bottom electrode. For both cases thermal stability up to 780°C with low leakage current has been shown. Band discontinuities between SiO 2 and WSi x were estimated from current–voltage measurements.