Scanning Tunneling Microscopy and Spectroscopy on Si(111)

Abstract

An overview is given on the application of scanning tunneling microscopy for a study of clean semiconductor faces, in particular, of Si(111). The theoretical models for interpretation of the measurements are discussed briefly and the experimental techniques are summarized. Results will be presented on different samples of Si(111). In addition to large scale 7 × 7 reconstructed Si(111), images are shown of (111) terraces, which develop a variety of reconstructions. For an interpretation of the results in terms of the topography of the surface the local electronic structure has to be considered. Information on the atomically resolved surface electronic structure may be obtained by scanning tunneling spectroscopy, where the tunneling current is determined locally as a function of sample bias voltage. The influence of energy and position on the tunneling probability is discussed.