MEV METAL-ION IMPLANTATIONS FOR BURIED LAYER FABRICATION IN SILICON

A review is given of MeV ion beam synthesis of deep-buried compound layers in silicon with special emphasis on the formation of buried metal silicide layers. The formation of buried NiSi2 layers by 6 MeV Ni high dose implantation and annealing is described in detail. The evolution of Ni concentration profiles, the dose-dependent interaction of implanted metal atoms and radiation damage, and the formation of the silicide phase are treated up to overstoichiometric doses. Layer formation during the anneal is described for both pure Ni implanted (111)Si wafers and for Ni irradiated Si/Si3N4/(100)Si silicon-on-insulator structures, leading to heteroepitaxial Si/NiSi2/Si systems and to Si/Si3N4/Si/NiSi2/Si multilayer sequences, respectively. The latter experiments possibly imply a new application of MeV implantations for the formation of buried layers.