Growth Kinetics and Boron-Doping of Very High Ge Content Si1-xGex for Sources and Drains Engineering

Abstract

We have studied the in-situ boron-doping of high Ge content Si1- xGex layers (x = 0.3, 0.4 and 0.5). Those layers have been grown at low pressure (20 Torr) and low temperature (600{degree sign}C to 650{degree sign}C) with a heavily chlorinated chemistry (in order to be selective versus SiO2 (isolation) and Si3N4 (sidewall spacers)). We have quantified the impact of the diborane flow on the SiGe layer crystalline quality, its resistivity, the SiGe:B growth rate and the apparent Ge concentration. We have also probed the in-situ boron and phosphorus doping of Si @ 750 {degree sign} C, 20 Torr with a chlorinated chemistry. All the know-how developed will be most handy for the formation of in-situ doped recessed or raised sources and drains.