RTCVD growth and applications of epitaxial Si_1-xGe_x alloys

Rapid thermal chemical vapor deposition (RTCVD) is a competing technology for the growth of Si_1-xGe_x strained-layer structures for the development of silicon-based heterojunctions. High-quality epitaxial films with growth temperatures as low as 600°C and 4.5 nm-period superlattices have been demonstrated without the use of ultrahigh-vacuum techniques. Narrow-bandgap-base heterojunction bipolar transistors made of Si/Si_1-xGe_x/Si have been shown to have superior characteristics compared to all-silicon homojunction devices, and extend the scaling limits of bipolar transistors. Finally, RTCVD strained Si_1-xGe_x films exhibit well-resolved band-edge photoluminescence-the first step on the way to developing silicon-based light-emitting devices.