On the source of silicon minority-carrier lifetime degradation during molecular beam heteroepitaxial growth of III-V materials

Abstract

A major hindrance to the development of devices integrating III-V materials on silicon is the preservation of its electronic quality. In this contribution, we report on the severe decrease in silicon bulk minority-carrier lifetime after heteroepitaxial growth of gallium phosphide, in our molecular beam epitaxy (MBE) system. The drop in lifetime occurs after annealing silicon above 500°C; we assign the increased recombination rate to extrinsic defect originating from highly mobile impurities diffusing from the MBE chamber. We show that the contaminant can be gettered by phosphorous diffusion. We investigate two approaches to protect the Si bulk lifetime by containing the contaminant to a part of the silicon that can be removed by etching. This provides a path to successful III-V growth on silicon.