The Growth of High Quality Epitaxial Silicon over Ion Implanted Buried Arsenic Layers

Abstract

High structural quality epitaxial Si layers have been grown over implanted As patterns. For As doses , it has been necessary either to implant into a heated substrate or to remove the damaged region prior to epitaxial growth. This can be conveniently done by diffusing in an oxygen ambient; consuming part of the damage by oxidation while diffusing the donor impurities away from the damaged silicon. Sheet resistivities of less than 10 ohms/□ have been attained as have minority carrier lifetimes over 20 μsec in the epitaxial layer, with no lifetime difference observed on control areas or regions grown over the buried layers. , photoresist and silicon contact masks have been successfully employed. For implantation doses of , driven to a junction depth of 3 μm, sheet resistivities of 20 ohms/□ were obtained. The existence of HF staining of the damaged region prior to annealing has been observed.