2008 Volume 49 Issue 7 Pages 1579-1588
Recently, a property of diamond as a semiconductor is focused on by many researchers. For the mass production, it is important to develop the manufacturing process. As it is thought that the ionic milling process has limitations, the application of gasification reactions with oxidizing gases such as CO2, H2O and O2 is the best option.
In this study, reaction behaviors of diamond at temperatures of more than 1273 K were investigated under a wide range of oxygen potentials, and the crystallographic relationship from diamond to graphite was clarified.
A graphite layer was formed on the surface of diamond under both Ar gas with an oxygen potential of less than 100 ppm, and a CO2-Ar mixture (30 vol%). The Raman spectrum consisted of the amorphous carbon and graphite. However, the graphite formed differed from ordinary graphite in the reactivity. Furthermore, the crystallographic relationship between diamond and graphite was determined to be (111)D||(002)G.