Heavily phosphorus-doped epitaxial Si deposited by low-temperature plasma-enhanced chemical vapor deposition

Abstract

Heavily P-doped Si layers have been grown at very low temperature (<600 °C) by rf plasma chemical vapor deposition. Films grown by vapor phase epitaxy (VPE) or solid phase epitaxy (SPE) are compared. By VPE growth, fully electrically activated films with a P concentration in excess of 1021 cm−3 and steep doping profiles (≤4 nm/dec) were obtained. SPE films are not fully activated and an anomalously fast P diffusion is observed during the crystallization at 600 °C. On the other hand, the Hall mobility of VPE films is significantly lower than that of SPE films.