Graphitization of a diamond surface upon high-dose ion bombardment

Results from structural and morphological studies, measurements of the sheet electrical resistance, and estimating resistivity ρm of a graphite-like conducting surface layer formed upon high-dose irradiation of the (111) face of a synthetic diamond with Ar+ ions at an energy of 30 keV and a target temperature of 400°C are presented. It is found that the orienting effect of the diamond lattice is visible in the suppression of the formation of graphite crystallites with axis c perpendicular to the surface. The thickness of the modified layer is 40–50 nm, and its sheet resistance is 0.5 kΩ/sq. Resistivity ρm = 20–25 μΩ m of the modified layer lies within the range of ρ values of graphite and glassy carbon materials.