Hydrogen-induced domain-wall structure on Si(113)

In-situ high resolution electron diffraction (SPA-LEED) and scanning tunnel ing microscopy (STM) measurements during the chemical vapor deposition grow th from disilane (Si2H6) on Si(113) show a variety of different surface rec onstructions, depending on the equilibrium hydrogen coverage on the surface adjustable by substrate temperature. At high H coverage, a regularly forme d missing row structure with light domain walls is observed. At low H cover age, STM images reveal large uncovered areas between several hydrogen-termi nated rows, changing the light domain wall structure into a heavy domain wa ll structure. The domain wall formation depends only on the equilibrium H c overage on the surface and is fully reversible with desorption of the hydro gen. The relation between the observed surface structures and thermal desor ption of H is shown in a phase diagram. The activation energy for the trans itions was found to be 2.1 eV and agrees well with the desorption energy fo r atomic hydrogen determined by growth oscillations. (C) 2000 Published by Elsevier Science B.V. All rights reserved.