Characterization of bias enhanced MWCVD diamond thin films

Abstract

Diamond films deposited by MWCVD (microwave assisted chemical vapor deposition) after bias enhanced nucleation have been characterized by Raman spectroscopy (RS), scanning electron microscopy (SEM) and electric measurements. The diamond/graphite ratio in the films, as measured by RS and verified by electric measurements, depends on the methane concentration during the growth step and the temperature in the bias stage. The higher the diamond content in the films, the better dielectric properties they exhibit. The dc conductivity of these films is always lower than those measured in films grown on scratched substrates. Thus, diamond films with low dc conductivities, similar to natural diamond, could be deposited choosing the appropriate bias nucleation conditions.