Structural and electrical properties of silicon dioxide layers with embedded germanium nanocrystals grown by molecular beam epitaxy

Abstract

A sheet of spherical, well-separated, crystalline Ge nanodots embedded in SiO2 on top of a p-(001)Si wafer was fabricated by molecular beam epitaxy (MBE) combined with rapid thermal processing and characterized structurally and electrically. The average size of the Ge nanodots was estimated to be 4.5 nm with an average aerial density of 3×1011 cm−2, situated at 4.4 nm in average away from the Si/SiO2 interface. Significant charge storage effects were observed through capacitance–voltage measurements of metal–oxide–semiconductor capacitors.