Abstract
Observation of angle-resolved electron stimulated desorption (ESD) from air-cleaved MgO (001) surface was carried out. Desorbed species have been analyzed by a quadrupole mass spectrometer (QMS) and by time-of-flight (TOF) methods. Most of the desorbed ions originate from adsorbates such as hydroxide or water. The angular dependence of the desorbed ions suggests adosorbed-site and -direction of adsorbates. To investigate some relations of the angular distributions and surface structures, the observation with the atomic force microscope (AFM) of MgO (001) surface was performed. AFM images show <100> aligned giant step lines whose heights are 3 to 4 nm. This result suggest that adsorbates at this giant step sites influence on the angular distributions of ESD ions.
