Study of hydrogen and methane modification of CVD diamond by XAS at the carbon K-edge

Abstract

Abstract The surface of a textured, (110) oriented, diamond film produced by chemical vapor deposition (CVD) was investigated using surface-sensitive X-ray absorption spectroscopy at the carbon 1s absorption edge. For surface modification, the film was exposed to different in-situ hot filament treatments involving atomic hydrogen and methane radicals. In the pre-edge absorption spectrum, we observe different resonances characteristic for transitions in non-diamond carbon species. They can be attributed to sp2-coordinated carbon atoms in amorphous or graphitic carbon phases and to C-H∗ resonances due to hydrocarbon surface components. The changes in the pre-edge structure during the hot-filament treatments are discussed in terms of hydrogen etching and growth of solid carbon.