Dimer pinning and the assignment of semiconductor–adsorbate surface structures

Abstract

It has been observed in scanning tunneling microscopy (STM) that the adsorption of molecules on the (001) surface of a Group IV semiconductor can lead to an asymmetric ordering of the dimers immediately adjacent to the adsorbate. This so-called pinning may occur along the dimer row on only one, or both sides of the adsorbate. Here we present a straightforward methodology for predicting such pinning and illustrate this approach for several different adsorbate structures on the Si(001) surface. This approach extends earlier work by including the effects of coupling across the adsorbate as well as the nearest-neighbor interactions between the chemisorbed dimer and its adjacent dimers. The results are shown to be in excellent agreement with the room temperature experimental STM data. The examples also show how this approach can serve as a powerful tool for discriminating between alternative possible adsorbate structures on a dimerized semiconductor (001) surface, especially in cases of molecular adsorption where the STM measurements provide insufficient details of the underlying atomic structure.

Document Details

Document Type
Pub Defense Publication
Publication Date
Feb 10, 2011
Source ID
10.1063/1.3551618

Entities

People

  • Daniel R. Belcher
  • Marian W. Radny
  • Oliver Warschkow
  • Phillip V. Smith
  • Steven R. Schofield

Organizations

  • Army Research Office
  • Australian Research Council
  • University College London
  • University of Newcastle
  • University of Sydney

Tags

Readers

  • Quantum spin resonance or Electron Paramagnetic Resonance spectroscopy.
  • Regression Analysis.
  • Thin Film Deposition Science.

Technology Areas

  • Microelectronics