Thermal Stability and Oxidation of Group IV Terminated (100) Diamond Surfaces

High resolution X‐ray photoelectron spectroscopy is used to explore the thermal stability of as‐prepared and oxidized silicon and germanium‐terminated (100) diamond surfaces which form two domain (3 × 1) surface reconstructions. The as‐prepared germanium and silicon‐terminated surfaces are stable up to 1200 °C, making them the most thermally stable surface termination for diamond (100). The oxidized forms of these surfaces can be created via exposure to O 2 , H 2 O or atmospheric conditions and retain the (3 × 1) surface symmetry. The thermal stability of the oxidized surfaces exhibit differing behavior. A 700 °C anneal is sufficient to liberate oxygen from the germanium‐oxide‐terminated (100) diamond surface, leaving the pristine germanium‐terminated surface, while the silicon‐oxide‐terminated surface is thermally stable up to 1200 °C, at which point both silicon and oxygen are removed.