Showing papers by "Jens Enevold Thaulov Andersen published in 1991"
TL;DR: In this article, the crystallographic and electronic structures of surfaces of the large-gap semiconductors SrTiO{sub 3}(100) and LaAlOµsub 3µ(100), and of the insulator MgO (100), were followed during the initial stages of a metal-beam deposition of yttrium metal at room temperature.
Abstract: The crystallographic and electronic structures of surfaces of the large-gap semiconductors SrTiO{sub 3}(100) and LaAlO{sub 3}(100), and of the insulator MgO (100), were followed during the initial stages of a metal-beam deposition of yttrium metal at room temperature. The techniques used are low-energy electron diffraction, Auger-, electron-energy-loss, and ultraviolet photoelectron spectroscopy. Yttrium grows epitaxially 1{times}1 on the MgO (100) surface and nonepitaxially on the LaAlO{sub 3}(100) and SrTiO{sub 3}(100) surfaces. Initially, below monolayer coverage, Y is strongly oxidized by the MgO(100) substrate. Near-monolayer yttrium coverages Y{sup 2+} is identified, and upon further Y deposition the oxidation state gradually changes further towards a lower value. Oxidation of an yttrium film on 1{times}1 MgO(100) results in changes around the Fermi level and changes in the core-level binding energies, but no changes in the upper valence band were observed.
7 citations
TL;DR: In this paper, a simple model for the calculation of surface elemental composition, surface impurity content and surface chemical termination in complex oxide crystal surfaces is presented based upon Auger electron spectroscopic measurements and takes electronic inelastic mean free paths or attenuation lengths and bulk crystallographic data into consideration.
6 citations
TL;DR: In this paper, a general procedure for Auger-analysis characterization of the modes of growth during deposition of metal thin films onto layer-structured crystalline substrates is presented, taking into account the crystallographic electron attenuation in both the overlayer structures and in the substrate layers, and it is found that the maximum Auger electronic escape-depth has a minimum at monolayer coverage.
3 citations