Determination of the Mean Absorption Potential of Si for Electrons by Energy Loss Spectroscopy

Abstract

Complex structure potentials of silicon for 111 systematic diffraction were measured by convergent beam electron diffraction technique (Kossel - Möllenstedt pattern). The imaginary mean potential and its different components were determined directly by measuring the energy loss spectra of transmitted elctrons by means of an imaging filter (GIF) installed in the electron microscope. The imaginary mean inner potential was estimated to be 0.63 eV. The component of the imaginary inner potential due to plasmon excitation was estimated to be 0.53 eV. Some low indexed Fourier components were determined by matching intensity simulations to Kossel-Möllenstedt patterns. The absorption potential due to thermal vibration was found to be in the order of the full Einstein model.