Angle resolved auger electron spectroscopy

• Main Author: Carr, P.
• Published: University of Oxford 1979
• Subjects: 543
• Online Access: http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.450778

This thesis describes a study of angular effects in Auger electron emission from solid surfaces using a specially developed instrument, based on a static high resolution electron energy analyser, that allows Auger currents to be measured with almost any combination of incident beam angles and emission angles. The rate of Auger production as a function of depth was first of all examined by measuring the Auger emission angular distributions, from clean non-crystalline surfaces, using a wide variety of incident beam conditions. The rate of Auger production was found to be constant within the escape depth providing 2.5 ≤ E_p/E_c ≤ 24. Further experiments on various surfaces, with overlayers present, showed that the form of the Auger emission angular distributions could be used to determine whether or not the overlayer was uniform, and also to estimate its thickness. The angular variations of each part of the copper M_2,3VV doublet were measured for the first time from a single crystal copper surface. It was shown that the initial state of the Auger electron profoundly affects the emission angular distributions and this provided evidence that band structure effects could not be ignored when describing the initial state of the Auger electron. The lack of structure in the silicon L_2,3VV emission angular distributions was thought to be partly due to Auger electron originating in different types of surface site in the silicon surface. The angular distributions of the high energy Auger signals exhibited pronounced structure, independent of the initial state of the Auger electrons that could be correlated with the Kikuchi patterns end channeling patterns obtained at similar energies. Much of the structure in these signals could be qualitatively understood using the dynamical theory of electron diffraction. Finally these techniques were used to study the growth forms of various evaporated metal films.