PHOTON-STIMULATED ION DESORPTION FROM SEMICONDUCTOR SURFACES

Photon-stimulated ion desorption (PSD) from chemically and physically modified Si and GaAs surfaces are investigated by using synchrotron ra diation. It is found that the ion species of desorption, their yields, and their kinetic energies are greatly changed depending on the bondi ng state of the surface atoms or adsorbates. These phenomena are cause d by PSD mechanism in which ion desorption is based on electronic tran sitions of surface atoms by photon absorption. In addition to reportin g our experimental results, we discuss the possibilities of using PSD for controlling surface structure on the atomic scale.