A Cause for SiC/SiO2 Interface States: The Site Selection of Oxygen in SiC

P. Deák, A. Gali, Z. Hajnal, Th Frauenheim, N. T. Son, E. Janzén, W. J. Choyke, P. Ordejón

Research output: Contribution to journalConference article

11 Citations (Scopus)


We show that in the SiC/SiO2 system the interface states in the lower half of the gap are the consequence of the behavior of oxygen in SiC. Investigating the elemental steps of oxidation on a simple model by means of ab initia density functional calculations we find that, in course of the oxidation, carbon-vacancy (Vc) - oxygen complexes constantly arise. The V c+O complexes have donor states around Ev+0.8 eV. Their presence gives rise to a thin transition layer which is not SiO2: but an oxygen contaminated Si-rich interface layer producing the aforementioned gap states.

Original languageEnglish
Pages (from-to)535-538
Number of pages4
JournalMaterials Science Forum
Publication statusPublished - Nov 24 2003
EventProceedings of the 4th European Conference on Silicon Carbide and Related Materials - Linkoping, Sweden
Duration: Sep 2 2002Sep 5 2002



  • Interface States
  • SiO
  • Theory

ASJC Scopus subject areas

  • Materials Science(all)
  • Condensed Matter Physics
  • Mechanics of Materials
  • Mechanical Engineering

Cite this

Deák, P., Gali, A., Hajnal, Z., Frauenheim, T., Son, N. T., Janzén, E., Choyke, W. J., & Ordejón, P. (2003). A Cause for SiC/SiO2 Interface States: The Site Selection of Oxygen in SiC. Materials Science Forum, 433-436, 535-538.