Refractory metals in submicron IC architecture

Abstract

Materials traditionally used in integrated circuits have limitations as those circuits reach submicron design rules. Refractory metals have found their place in very-large-scale-integration device technologies, and an experimental program involving the use of tungsten as a gate material has been undertaken, with special emphasis on purity requirements. Bias temperature stress capacitance-voltage measurements show that very low levels of mobile ion contamination can be obtained in metal oxide semiconductor capacitors with tungsten gates sputtered from a special high-purity target.