Thermal Stability of CoSi2 on Submicron Polycrystalline Silicon Lines

The thermal stability of CoSi2 layers on undoped, B- and As-doped, submicron-sized polycrystalline Si lines has been investigated. It is found that the highest thermal stability is obtained for undoped poly-Si lines. The thermal stability of the silicide layers on As- or B-doped lines is largely improved if an additional Ge implant is performed prior to Co sputtering which amorphizes the complete Si layer which is consumed during silicidation.