Effects of photon irradiation on the chemical state of a (NH 4)2Sx-treated GaAs surface have been investigated using photoemission and photon-stimulated desorption (PSD) spectroscopic techniques with synchrotron radiation (SR). It is shown that a sulfur-passivation overlayer on the (NH4)2S x-treated GaAs surface is readily removed by irradiating SR in the vacuum-ultraviolet (VUV) region onto the surface, suggesting the possibility of cleaning the sulfur-passivated GaAs surface by VUV irradiation. The dominant PSD ion product that desorbs from the sulfur-passivated GaAs surface during VUV irradiation is found to be H+. No desorption of sulfur ions is observed, which suggests that sulfur adatoms desorb as neutral species.
ASJC Scopus subject areas
- Physics and Astronomy (miscellaneous)