Nitrogen, oxygen, and hydrogen bonding and thermal stability of ambient exposed nitrogen-terminated H-diamond (111) surfaces studied by XPS and HREELS

•Oxygen adsorption from the ambient depends on the structural defect density on the Di(111) surface caused by the nitrogen plasma interaction.•Nitrogen and oxygen exist in mostly a single bonding configuration on low damage surface.•Hydrogen co-adsorbs alongside N and O onto the Di(111) surfaces upon nitrogen plasma exposure. We report on the chemical composition, bonding, and in-vacuum thermal stability (up to 1000 °C) of nitrogen plasma terminated H-Diamond(111) (H-Di(111)) surfaces followed by ambient exposure. The nitrogen-plasma exposures include radio frequency (RF) (at pressure: 3 × 10−2 (damaging) and 7 × 10−2 Torr (non-damaging)) and microwave (MW) nitrogen plasmas and studied by X-ray photoelectron spectroscopy (XPS) and high resolution electron energy loss spectroscopy (HREELS). The largest nitrogen intake was observed upon exposure to RF(N2) damaging plasma, followed by MW(N2) and non-damaging RF(N2) plasmas. A similar trend follows the adsorption of adventitious oxygen. The XPS analysis shows that most of the adventitious oxygen is adsorbed in a COx configuration upon nitride surfaces exposure to ambient conditions. However, upon high temperature annealing of the damaging RF(N2) plasma exposed surface, some NOx (species) were detected by XPS. From the HREELS analysis, the hydrogen adsorbed on the H-Di(111) is not fully removed by exposure to the different nitrogen plasmas. These measurements show that NH(ads) species are formed on the surface and are desorbed upon vacuum annealing in the 500–700 °C range. This study may be of importance in all ex-situ applications influenced by the near-surface physicochemical and electronic properties of nitrogen-terminated H-Di(111) surfaces. [Display omitted]