Reduction of epitaxial alignment in n(+)-p poly-Si emitter diode due to gettering of P and As by Ar implantation

Abstract

It is demonstrated that Ar implantation can retard the epitaxial realignment of poly-Si/Si in an As- or P-doped n(+)-p poly-emitter diode during BF2 implantation. This is believed to be due to the gettering of As, P, and F by bubble-like defects created by the Ar implantation used to reduce the pile-up of these dopants at the poly-Si/Si interface. Consequently, there is less break-up of the interface oxide, resulting in a reduction in epitaxial realignment.