Electron-stimulated conversion of chemisorbed O to Al2O3 on Al(111)

Abstract

The transformation of a chemisorbed O layer on the Al(111) surface into Al2O3 under electron impact has been monitored by high-resolution electron energy-loss and x-ray photoelectron spectroscopies. Electron irradiation (100 eV) of chemisorbed O was observed to cause spectroscopic changes in the surface layer indicative of oxide formation. The energy transfer from the electrons to the chemisorbed O atoms through electronic excitations, leading to vibrationally excited adsorbed particles, is proposed to be responsible for the observed conversion of chemisorbed oxygen to Al2O3. The cross section for this electron-induced process is estimated to be 2 × 10-19 cm2 for 100 eV electrons. © 1999 American Institute of Physics.