PREPARATION AND CHARACTERIZATION OF ULTRA-THIN COBALT SILICIDE FOR VLSI APPLICATIONS

Ultra-thin cobalt silicide (CoSi2) was formed from 10 nm cobalt film b y solid phase reaction of Co and Si by use of rapid thermal annealing (RTA). The Ge+ ion implantation through Co film caused the interface m ixing of the cobalt film with the silicon substrate and resulted in a homogeneous silicide layer. XRD was used to identify the silicide phas es that were present in the Nm. The metallurgical analysis was perform ed by RES. XRD and RES investigations showed that final RTA temperatur e should not exceed 800 degrees C for thin (< 50 nm) CoSi2 formation.