AVS 51st International Symposium
    Surface Science Wednesday Sessions
       Session SS2-WeM

Paper SS2-WeM8
Hydrogen Interaction with a Si(113)-3x2 Surface

Wednesday, November 17, 2004, 10:40 am, Room 210C

Session: Semiconductor Surface and Interface Structure
Presenter: M. Yoshimura, Toyota Technological Institute, Japan
Authors: M. Yoshimura, Toyota Technological Institute, Japan
K. Mamiya, Toyota Technological Institute, Japan
K. Ueda, Toyota Technological Institute, Japan
Correspondent: Click to Email
Since the Si(113) surface is thermally stable and has a low energy compared to that of the low-index surfaces such as Si(111) and Si(001), it is expected to a good substrate for epitaxy in semiconductor technology. The clean surface reconstructs into a 3 x 2 superstructure consisting of pentamers and adatoms, as was proposed by Dabrowski et al.@footnote 1@ Each 3 x 2 cells contain a subsurface interstitial located below one of the tetramers, which lowers the total surface energy. On the other hand, hydrogen termination is one of important techniques in the silicon-based device processes. However, hydrogen interaction with the Si(113) has been studied only by spectroscopic measurements such as electron energy loss spectroscopy (EELS)@footnote 2@. Here, we report ultrahigh vacuum scanning tunneling microscopy (UHV-STM) study of the atomic hydrogen adsorption onto the clean Si(113)-3 x 2 surface on an atomic scale. A Si(113) surface was cleaned by a conventional procedure and was exposed at room temperature to atomic hydrogen by cracking of hydrogen molecules using a hot tungsten filament. After 10 L exposure, the reduction in the density of states around Fermi level was confirmed by scanning tunneling spectroscopy (STS). STM images revealed clearly that some adatoms were missing and some pentamers changed their image contrast, probably due to hydrogen adsorption at the surface dangling bonds of the corresponding sites. The clustering was not observed up to this exposure level. Based on the results of STM/STS together with low-energy electron diffraction (LEED), we discuss the initial adsorption processes of atomic hydrogen on Si(113)-3x2 at an atomistic level. @FootnoteText@ @footnote 1@ J. Dabrowski et al., Phys. Rev. Lett. 73 (1994) 1660.@footnote 2@ K. Jacobi and U. Meyer, Surf. Sci. 284 (1993) 223.