Local hetero-epitaxial diamond formed directly on silicon wafers and observed by high-resolution electron microscopy

Abstract

Diamond films were synthesized by the hot-filament chemical vapour deposition (HFCVD) method on Si(100) substrates with surface biasing pre-treatment. Evidence has been obtained from high-resolution cross sectional electron microscopy (HREM) that the diamond films grown on Si wafers showed localized epitaxy. There is an angle of approximately 7.3 degrees between Si(100) and D(100) hetero-epitaxial crystalline planes. The same type of twins (coherent twin boundaries of type Sigma =3) exists on and near the interface. It is shown that the pre-treatment of the substrate is a key factor for the localized hetero-epitaxy of diamond films on Si wafers.