Scanning tunneling microscopy of in situ cleaved and hydrogen passivated Si(110) cross-sectional surfaces

Abstract

Scanning tunneling microscopy (STM) is used to study the preparation of Si(110) cross-sectional surfaces. Atomically flat Si(110) cleavage faces with typical terrace widths of 20 nm are achieved in ultrahigh vacuum by partial pre-cleaving ex situ. The initially disordered surfaces are found to order upon annealing and the observed reconstructions are discussed. Passivation of electronic surface states in the band gap is performed by atomic-hydrogen exposure and characterized by STM conductance imaging and spectroscopy. Cross-sectional imaging and spectroscopy of Si(001) p n doping superlattices is demonstrated, and a comparison is made between results from in situ prepared surfaces and those from ex situ cleaved and HF-dipped samples. © 1995.