ULTRATHIN SILICIDE FORMATION FOR ULSI DEVICES

Recently the growth of epitaxial CoSi2 layers was demonstrated using t he oxide mediated epitaxy (OME) technique. A thin SiOx interlayer, gro wn in a peroxide-containing aqueous solution, induced the growth of ne arly perfect CoSi2 on practically all surfaces of Si, With deposited c obalt, a optimum thickness range of 1-3 nm was observed, independent o f the doping level and the orientation of the silicon. After the OME g rowth, the SiOx layer was found to remain largely on the surface and a ct as a cap of the silicide layer. An interesting result of the surfac e oxide cap was a significant re-evaporation of cobalt observed during deposition at elevated temperatures, Thicker (10-30 nM). excellent qu ality, CoSi2 single crystal thin films were grown by repeated growth s equences on Si(100), (110), (111), (211) and (511). Additionally OME g rowth was found nor to depend on linewidth and doping level, making it an attractive technique for ULSI applications.