Passivation of TiO 2 by ultra-thin Al-oxide

Th Dittrich, H. J. Muffler, M. Vogel, T. Guminskaya, A. Ogacho, A. Belaidi, E. Strub, W. Bohne, J. Rohrich, O. Hilt, M. Ch Lux-Steiner

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The passivation of sol-gel TiO 2 by ultra-thin layers of Al-oxide has been investigated using transient and spectral photovoltage (PV) techniques. The ultra-thin layers of Al-oxide were prepared by the ion-layer gas reaction (ILGAR) technique and modified by thermal treatments in air, vacuum or Ar/H 2 S atmosphere. The samples where characterized by elastic recoil detection analysis (ERDA), X-ray photoelectron spectroscopy (XPS), and contact potential difference (CPD) technique. Without an Al-oxide surface layer, electronic states in the forbidden gap of TiO 2 are formed during thermal treatments in vacuum and Ar/H 2 S. The trap density is strongly reduced at the TiO 2 /Al-oxide interface. The formation of electronic defects is prevented by a closed ultra-thin layer of Al-oxide.

Original languageEnglish
Pages (from-to)236-243
Number of pages8
JournalApplied Surface Science
Issue number1-4
Publication statusPublished - 15 Feb 2005



  • Al-oxide
  • Passivation
  • Photovoltage
  • Titania

ASJC Scopus subject areas

  • Chemistry(all)
  • Condensed Matter Physics
  • Physics and Astronomy(all)
  • Surfaces and Interfaces
  • Surfaces, Coatings and Films

Cite this

Dittrich, T., Muffler, H. J., Vogel, M., Guminskaya, T., Ogacho, A., Belaidi, A., Strub, E., Bohne, W., Rohrich, J., Hilt, O., & Lux-Steiner, M. C. (2005). Passivation of TiO 2 by ultra-thin Al-oxide Applied Surface Science, 240(1-4), 236-243.