Anomalous Diffusion in Non-Metals (Origin and Effects of Internal Electric Fields),

Abstract

When electrically active impurities or defects diffuse in a material with a band gap > 10 kT, the changing concentration of these ions may result in internal electric fields which will significantly alter the diffusion process, and result in gross misinterpretation of diffusion experiments. Equations are derived which describe the diffusion of interstitial impurities in such a system, and which take proper account of compensating immobile impurities. A technique for numerical solution of these equations is described and the results of calculations for the case of H(+) in TiO2 are presented. These calculations predict a large enhancement of the overall diffusion rate and a very distinctive concentration profile. Experimental results for the H(+)-TiO2 system are presented, which agree quantitatively with calculations. (Modified author abstract)

Document Details

Document Type
Technical Report
Publication Date
Jan 01, 1974
Accession Number
AD0787667

Entities

People

  • J. W. Deford
  • O. W. Johnson

Organizations

  • University of Utah

Tags

DTIC Thesaurus Topics

  • Absorbers (Materials)
  • Abstracts
  • Advanced Materials
  • Band Gaps
  • Band Structures
  • Diffusion
  • Electric Fields
  • Energy Bands
  • Engineered Materials
  • Equations
  • Impurities
  • Materials
  • Physical Properties
  • Solid State Properties

Readers

  • Materials Science and Engineering.
  • Plasma Physics.
  • Theoretical Analysis.