Surface defect states analysis on diamond by photoelectron emission yield experiments

Abstract

Total photoyield spectroscopy (TPYS) was applied on partially hydrogen-terminated IIa (001) diamond surfaces, to investigate the variation of the negative electron affinity (NEA) and formation of defects by hydrogen evaporation. According to the results, we find that the amplitude of negative electron affinity is not changed by partial hydrogen evaporation. The negative electron affinity of residual hydrogen-terminated areas is maintained at around − 1.0 eV. Surface states are generated by partial hydrogen desorption at around 1.6 ± 0.1 eV above the valence band maximum. Hydrogen-free surfaces exhibited positive electron affinity. These experiments demonstrate that TPYS is a promising technique for surface defect characterization.