Microwave plasma doping: Arsenic activation and transport in germanium and silicon

Microwave RLSA (TM) plasma doping technology has enabled conformal doping of non-planar semiconductor device structures. An important attribute of RLSA (TM) plasma doping is that it does not impart physical damage during processing. In this work, carrier activation measurements for AsH3 based plasma doping into silicon (Si) and germanium (Ge) using rapid thermal annealing are presented. The highest carrier concentrations are 3.6 x 10(20) and 4.3 x 10(18) cm(-3) for Si and Ge, respectively. Secondary ion mass spectrometry depth profiles of arsenic in Ge show that intrinsic dopant diffusion for plasma doping followed by post activation anneal is much slower than for conventional ion implantation. This is indicative of an absence of defects. The comparison is based on a comparison of diffusion times at identical annealing temperatures. The absence of defects, like those generated in conventional ion implantation, in RLSA (TM) based doping processes makes RLSA (TM) doping technology useful for damage free conformal doping of topographic structures. (C) 2016 The Japan Society of Applied Physics