Formation of nanometer-size high-density pits on epitaxial diamond (100) films

We report the formation of pits having widths of approximately 10 nm and a density of 2.5 × 1011/cm2 on epitaxial diamond (100) films. The pits are formed by etching the films using atomic hydrogen at a substrate temperature of approximately 500 °C. Exposure to oxygen followed by etching with atomic hydrogen forms additional pits. We propose that the high-density pits are formed due to etching that occurs both perpendicular and parallel to the surface.