PHOSPHORUS GAS DOPING IN GAS SOURCE SILICON-MBE

Phosphorus doping in the range 1019-1020ohm cm-3 was successfully achieved using 5% PH3 diluted by SiH4 as a doping gas in disilane gas source silicon-MBE. The phosphorus concentration was proportional to the PH3 flow rate. However, a decrease in the epitaxial growth rate was observed with increasing PH3 flow rate. In-plane doping level uniformity was much improved in comparison with antimony ionized doping. An abrupt doping profile was observed by secondary ion mass spectroscopy (SIMS) when the surface was first exposed to the silicon flux. Selective epitaxial growth of a phosphorus-doped layer was found. © 1990.