Effect of boron on formation of interstitial-related luminescence centres in ion implanted silicon

Abstract

The presence of boron in silicon has been shown to have a deleterious effect on the luminescence of interstitial-related centres, particularly the W-centre which is often observed after ion implantation and a low temperature anneal. Competition between silicon-interstitial and boron-interstitial centre formation is considered to be a possible mechanism underlying this dramatic reduction. Previous work on silicon implantation of boron-doped substrates is extended to examine the effect of B implantation itself on W-centre formation. W centres formed via the implantation of B and a low temperature anneal and via a Si implant over an activated B-implant profile followed by low temperature anneal are compared. These studies contrast the effects of boron and silicon implantation and examine the effect of overlapping implantation profiles. Studying the effect of boron on optical centre formation provides insight into defect interactions in silicon and new data for theoretical modelling.