THERMAL-STABILITY AND DOPANT DRIVE-OUT CHARACTERISTICS OF COSI2 POLYCIDE GATES

BF2-implanted CoSi2 Polycide gates that are stable at high temperatures up to 1000-degrees-C have been fabricated. The use of CoSi2 polycide as a boron diffusion source was evaluated using a metal-oxide-semiconductor capacitor structure on a p-type Si substrate. This structure is useful in monitoring the diffusion of the electrically activated dopants from the silicide towards the polycrystalline silicon-SiO2 interface. Our results show that using BF2-implanted CoSi2 as a diffusion source is effective in doping polycrystalline silicon gates degenerately without any degradation of the polycide resistivity.