The study of H+ ion bombardment on the surface of diamond grains

Diamond was nucleated on mirror-polished silicon substrate by the bias-enhanced nucleation (BEN) method and grown by microwave-plasma chemical vapor deposition (MWPCVD) technology. The H+ ion beam was formed by applying negative potential to the substrate. Repeated bombardment and growth processes were performed on the diamond grains. Changes in morphology, and etching and growth rates for the diamond grains were locally studied by scanning electron microscopy (SEM). The results showed that the area of (001) facets for a (001)-textured diamond grain obviously increased. Mechanisms for etching and growth of the diamond grains are suggested. This work describes a method for obtaining high-quality and large-area (001)-oriented diamond thin film and adds to the understanding of the balanced process of etching and growth during CVD diamond deposition under ion bombardment.