High Temperature Defect Chemistry of Aluminum Oxide.

Abstract

The high temperature defect structure of aluminum oxide was investigated by measurements on single crystals containing known amounts of cobalt. These include high temperature measurements of the conductivity and the emf of concentration cells as functions of oxygen pressure and temperature, and low temperature measurements of optical absorption and electron spin resonance. Analysis of the results leads to a defect model dominated by interstitial aluminum and divalent substitutional cobalt, to parameters of thermodynamic constants regulating the formation of point defects and the oxidation-reduction of cobalt from divalent to trivalent and vice versa, and to the position of levels of cobalt in the forbidden gap. A similar model applies to aluminum oxides doped with iron.

Document Details

Document Type
Technical Report
Publication Date
Apr 01, 1975
Accession Number
ADA011984

Entities

People

  • F. A. Kroger

Organizations

  • University of Southern California

Tags

DTIC Thesaurus Topics

  • Aluminum
  • Aluminum Oxides
  • Chemistry
  • Crystals
  • Electron Spin Resonance
  • High Temperature
  • Low Temperature
  • Magnetic Resonance
  • Measurement
  • Optical Absorption
  • Oxidation
  • Oxides
  • Point Defects
  • Resonance
  • Single Crystals
  • Spin Resonance

Fields of Study

  • Materials science

Readers

  • Materials Science and Engineering.
  • Surface Engineering/Surface Coating Technology.

Technology Areas

  • Microelectronics