Atomic-structure determination of diamond using Auger-electron diffraction.

Abstract

The surface structure of diamond is determined by comparing angle-resolved Auger-electron spectroscopy data to a theoretical model of electron diffraction in a cluster. The diffraction pattern of carbon KVV Auger-electron emission at 265 eV from a diamond(100) surface was obtained in an ultrahigh vacuum chamber. The polar scan curves of the experimental data at azimuthal angles 0\ifmmode^\circ\else\textdegree\fi{}, 15\ifmmode^\circ\else\textdegree\fi{}, 30\ifmmode^\circ\else\textdegree\fi{}, and 45\ifmmode^\circ\else\textdegree\fi{} are compared to theoretical predictions obtained using a single scattering cluster model. The calculated polar intensity distributions are a fairly sensitive function of surface structure. Optimal agreement with experiment occurs when there is a (2\ifmmode\times\else\texttimes\fi{}1) reconstruction at the diamond surface and there is a perpendicular expansion of 0.015(\ifmmode\pm\else\textpm\fi{}0.001) \AA{} between layers 1 and 2, 0.010(\ifmmode\pm\else\textpm\fi{}0.003) \AA{} between layers 2 and 3 and 0.005(\ifmmode\pm\else\textpm\fi{}0.005) \AA{} between layers 3 and 4. \textcopyright{} 1996 The American Physical Society.