Photoemission and density functional theory study of Ge(100): Clean surface and Yb-induced (2x4) reconstruction

Research output: Contribution to journalArticle

Abstract

Clean and metal-adsorbed (100) surfaces of group-IV semiconductors, such as Si and Ge, often exhibit electronically and structurally similar reconstructions. However, the fundamental bulk properties of group-IV materials can have an impact on particular features of such systems, which are related, e.g., to final-state relaxation in photoemission and thus determine their spectral line shape. Here we have studied Yb/Ge(100)(2 x 4) reconstruction as well as clean Ge(100) surface by high-resolution photoelectron spectroscopy and ab initio calculations. An atomic geometry of both surfaces is thoroughly investigated. A detailed analysis of Ge 3d core-level photoemission, atomic origins of surface-shifted components, and final-state screening effects is presented. In particular, it is demonstrated that the core-hole screening plays an essential role in Ge 3d measurements, and that its amount in the complete screening model correlates well with the core-level binding energy of respective Ge atoms in the initial state. The results are discussed in the proper context of related reconstructions on Si(100). (C) 2013 Elsevier B.V. All rights reserved.

Details

Authors
  • M. Kuzmin
  • M. P. J. Punkkinen
  • P. Laukkanen
  • R. E. Perala
  • J. J. K. Lang
  • J. Dahl
  • Johan Adell
  • K. Kokko
Organisations
Research areas and keywords

Subject classification (UKÄ) – MANDATORY

  • Physical Sciences
  • Natural Sciences

Keywords

  • Germanium, Ytterbium, Photoelectron spectroscopy, DFT calculation, Atomic structure, Surface core-level shift
Original languageEnglish
Pages (from-to)88-96
JournalSurface Science
Volume615
Publication statusPublished - 2013
Publication categoryResearch
Peer-reviewedYes