Direct observation of lattice strain in Si1-xGex/Si crystals using planar channeling patterns

This paper describes the direct observation of lattice strain in channeling patterns produced by 3 MeV protons transmitted through strained Si1-xGex/Si bilayers close to planar channeling directions. Blocking lines arising from each layer can be separately resolved at certain alignments, whereas only single lines, or bands of bright and dark lines are visible at other alignments, The conditions under which planar channels can be resolved are determined. The measured angular separation between the resolved planar channels in the channeling patterns is in good agreement with the interface rotation angle measured using backscattering spectrometry, The conditions under which this procedure can be used to measure the interface rotation angle are discussed. (C) 1997 Elsevier Science B.V.