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Optical and Electronic Properties of Modified Amorphous Materials

  • R. Flasck
  • M. Izu
  • K. Sapru
  • T. Anderson
  • S. R. Ovshinsky
  • H. Fritzsche
Part of the Institute for Amorphous Studies Series book series (IASS)

Abstract

The thermal activation energy, AE, of the conductivity in amorphous chalcogenide semiconductors is usually about half of the optical gap energy E. This is commonly interpreted as (intrinsic) conduction at the mobility edge by carriers whose concentration is governed by the Fermi energy EF which is pinned near the gap center. Small changes in glass composition and the presence of impurities usually have little effect on the properties except for small changes in EO and AE with composition. The insensitivity to impurities is ascribed to the fact that in a material lacking long-range order each foreign atom can satisfy its valency requirement,(1) and, thus, will not act as an electrically active center. The origin of the various states in the gap (DECs) (2,3) and the pinning of EF is attributed to those DECs which are inherent valence alternation defect centers.

Keywords

Seebeck Coefficient Chalcogenide Glass Thermal Activation Energy Mobility Edge Foreign Atom 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

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Copyright information

© Plenum Press, New York 1991

Authors and Affiliations

  • R. Flasck
    • 1
  • M. Izu
    • 1
  • K. Sapru
    • 1
  • T. Anderson
    • 1
  • S. R. Ovshinsky
    • 1
  • H. Fritzsche
    • 2
  1. 1.Energy Conversion Devices, Inc.TroyUSA
  2. 2.Department of PhysicsUniversity of ChicagoChicagoUSA

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