Diamond surfaces were analyzed by high resolution X-ray photoelectron
spectroscopy (XPS). As X-ray source, a monochromatized Al Kα anode (1486.6 eV) was used calibrated versus the Au 4f7/2 peak located at 84.0 eV. The spectrometer was equipped with an EA 125 hemispherical analyzer. The pass energy was 20 eV, corresponding to an energy absolute resolution of 0.6 eV. Measurements were done at 51° detection angle. The XPS data of the C1s spectral region were corrected
thanks to a Shirley-background subtraction. To obtain the peak positions and relative contributions of chemically shifted components, a fitting procedure was applied using Voigt functions. Raman analyses were carried out with a LAbRAM HR Jobin Yvon. A 514 nm excitation wavelength associated to a confocal aperture of 100 μmand 120 s of acquisition time were used.