Phosphorus doped molybdenum silicide technology for LSI applications

Phosphorus doped molybdenum silicide film as gate electrodes, interconnecting material, and an impurity diffusion source for LSIs has been investigated. The phosphorus doped silicide films were deposited by co-sputtering of Mo and Si in PH3/Ar ambient. Phosphorus is able to diffuse from the film into silicon in O2annealing and the contact resistance between silicide and silicon substrate is below 2 × 10^-6ohm-cm²after high temperature annealing up to 1100°C. Reliability of MOS FETs is as good as polysilicon gates and the shift of threshold voltage is below ±20mV under stress condition of <±2.5MV/cm for 1000 hours at 150°C.