Accession Number : ADA189094

Title :   The Magnitude of Secondary Electron Contributions in Photon Stimulated Desorption.

Descriptive Note : Interim technical rept.,

Corporate Author : GEORGE WASHINGTON UNIV WASHINGTON D C DEPT OF CHEMISTRY

Personal Author(s) : Ramaker, David E ; Madey, T E ; Kurtz, R L ; Sambe, Hideo

PDF Url : ADA189094

Report Date : Dec 1987

Pagination or Media Count : 5

Abstract : Recent reports on the extent of secondary electron contributions in electron/photon stimulated desorption (ESD/PSD) appear to be contradictory. JAEGER et al. suggested that secondary electrons provide the dominant contribution to the H+ yield from NH3/Ni and called the process x-ray induced ESD (XESD). Others have concluded that the XESD process is the dominant mechanism in the PSD of N+ and O+ ions from the mixed condensed gases such as N2 and O2 and in the PSD of H+ ions from OH/YbO-Sm. On the other hand, considerable evidence exists in the literature for the dominance of the direct photon excitation mechanisms. This paper presents a re-examination of the three systems mentioned above where a dominant XESD effect has been postulated to determine the validity of the conclusions previously reached. Keywords: Electra simulated desorption; Photon stimulated desorption; Secondary electrons.

Descriptors :   *DESORPTION, ELECTRONS, EXCITATION, IONS, PHOTONS, SECONDARY EMISSION, SIMULATION, STIMULATION(GENERAL), NITROGEN, OXYGEN, HYDROGEN, AMMONIA, SUBSTRATES, NICKEL, X RAYS

Subject Categories : Physical Chemistry

Distribution Statement : APPROVED FOR PUBLIC RELEASE