Formation of Nanoscale Diamond Particles without Substrate Heating by Cathodic Arc Deposition

A carbon film grown at room temperature using a cathodic arc process in ambient gases such as N 2 and He was investigated by Raman spectroscopy and scanning electron microscopy (SEM). Diamond particles were found to be formed at a constant total pressure of 10 -2 Pa, while graphite-like carbon was grown at a lower pressure of around 10 -3 Pa in the lower P (He) / P (Total) region and tetrahedral amorphous carbon was grown at a higher pressure such as 10 -1 Pa. The diamond particles were randomly distributed in the film and had sizes in the range of 50–200 nm.