Epitaxial Si(001) grown at 80–750 °C by ion-beam sputter deposition: Crystal growth, doping, and electronic properties

Abstract

Epitaxial undoped and Sb-doped Si films have been grown on Si(001) substrates at temperatures Ts between 80 and 750 °C by ultrahigh-vacuum Kr+-ion-beam sputter deposition (IBSD). Critical epitaxial thicknesses te in undoped films were found to range from 8 nm at Ts=80 °C to ≳1.2 μm at Ts≥300 °C, while Sb incorporation probabilities σSb varied from unity at Ts≲550 °C to ≂0.1 at 750 °C. These te and σSb values are approximately one and one to three orders of magnitude, respectively, higher than reported results achieved with molecular-beam epitaxy. Temperature-dependent transport measurements carried out on 1-μm-thick Sb-doped IBSD layers grown at Ts≥350 °C showed that Sb was incorporated into substitutional sites with complete electrical activity and that electron mobilities in films grown at Ts≥400 °C were equal to the best reported results for bulk Si.