Silicon-germanium-carbon alloys extending Si based heterostructure engineering

Abstract

SiGe epitaxial growth on Si has been of interest for a number of years. In this work we consider the addition of 1 to 6% C into both Si and SiGe epitaxial material. We have used a solid, and a gas source, (acetylene), within a solid source SiGe molecular beam epitaxy system to produce a C flux. We have produced high-crystalline-quality Si1-yCy and Si1-x-yGexCy material using both approaches. In addition we demonstrate strain-symmetrical short-period superlattice structures grown on (100) Si with high Ge compositions ranging from 20% up to 100% Ge, at 100% Ge the Ge/Si1-xCy superllatice has an interface mismatch of 7%.