Sulfur-treated InP surfaces studied by soft X-ray photoemission spectroscopy

Sulfur treatment with (NH/sub 4/)/sub 2/S/sub x/ is regarded as an efficient surface passivation technique to reduce surface states on both GaAs and InP. In this study, we measured S1s photoelectron spectra by using synchrotron radiation soft X-rays, which have no spin-orbit splitting, to investigate the effect of water rinsing and the change in the sulfur chemical bond by annealing in vacuum after the (NH/sub 4/)/sub 2/S/sub x/-treatment. Reflection high-energy electron diffraction (RHEED) patterns were recorded to obtain information about the surface structure of the samples before the photoelectron measurements.