Abstract
A crystalline carbon nitride film was successfully synthesized on a sapphire substrate by microwave plasma CVD method. The deposition was carried out using a CH4 /N2 plasma maintaining the substrate temperature at around 780 °C. We did not use a Si substrate but a sapphire substrate to prevent Si contamination that forms Si3N4,SiC, SiCN or others in the deposited film. The deposited film was characterized by SEM, XPS, Raman spectroscopy, XRD and Nanoindenter. The X-ray diffraction pattern reveals that the deposited film consists of α–C3N4 crystals, and the Raman spectrum indicates characteristic peaks at around 380 and 420 cm-1. The hardness of the carbon nitride film is estimated over 50 GPa by Nanoindenter.
