Diamond thin film grown homoepitaxially on diamond (001) substrate by microwave plasma CVD method studied by reflection high-energy electron diffraction and atomic force microscopy

Abstract

A diamond thin film surface produced homoepitaxially on C(001) substrate by microwave plasma chemical vapor deposition (CVD) has been studied using reflection high-energy electron diffraction (RHEED) and atomic force microscopy (AFM). The RHEED patterns showed C(001)2×1/1×2 double-domain structure. Wide RHEED patterns with many Kikuchi patterns qualitatively show the high crystallinity of the diamond thin film. The AFM images taken from the same sample with atomic-scale resolution in air showed mostly {001} surface; 2×1 but locally 1×1 structure, which is in agreement with the RHEED measurement, although {111} surface was observed rarely. The {111} plane observed rarely was tilted by 15.7° from the (001) substrate, which can be explained by the twinning structure in the thin film. The local 2×1 structure on the {111} plane appears by scanning with the AFM tip; tip-induced surface reconstruction.