Reversible Conductivity Transformations in Chalcogenide Alloy Films

  • E. J. Evans
  • J. H. Helbers
  • S. R. Ovshinsky
Part of the Institute for Amorphous Studies Series book series (IASS)


Certain amorphous chalcogenide alloys, such as Ge15Te85, exhibit metastable conductivity. These reversible structural changes in amorphous alloys entailing variation in order and conductivity have been made the basis of memory devices.(1) In this paper, we present our observations on induced conductivity transformation from one state to another. Because the conductivity involves structural changes in the bulk we relate our results to those obtained from calorimetric (2) and structural investigation (3) on the same materials. We also present measurements on the electrical characteristics of memory switches.


Threshold Voltage Amorphous Alloy Conductive State High Resistance State Memory Material 
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Copyright information

© Plenum Press, New York 1991

Authors and Affiliations

  • E. J. Evans
    • 1
  • J. H. Helbers
    • 1
  • S. R. Ovshinsky
    • 1
  1. 1.Energy Conversion Devices, Inc.TroyUSA

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