Electronic properties of amorphous dielectric films

doi:10.1016/0040-6090(67)90004-1

Thin Solid Films

Volume 1, Issue 3, November 1967, Pages 213-234

https://doi.org/10.1016/0040-6090(67)90004-1 Get rights and content

Abstract

The effect of the amorphous and glassy structure of most dielectric films on their electrical characteristics is discussed with reference to experimental results obtained, in particular, with amorphous germanium. The dangers of interpreting the results too rigidly in terms of conventional “crystalline” concepts are pointed out. The Poole-Frenkel and Schottky mechanisms are discussed in detail and the shortcomings of the accepted picture of the former in amorphous materials are dealt with. It is concluded on the basis of available evidence that it is not yet possible to rule out definitively either one or the other of these effects in any particular case. The evidence for electronic hopping in dielectric films is discussed and it is concluded that in many instances this is the dominant conduction mechanism at low fields and moderate to high frequencies. The existence of apparently unexplained phenomena is pointed out which result in power-law dependence of current on voltage with high exponents of the order 6–16. It is thought that these phenomena are not likely to be simple manifestations of space-charge-limited flow. The review concludes with a discussion of electrical contacts to dielectric films and of the ways of distinguishing between ionic and electronic transport processes.

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Citation Excerpt :
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ReviewsElectronic properties of amorphous dielectric films

Abstract

Advan. Phys.

Advan. Phys.

Phys. Rev.

Phys. Rev.

Phys. Rev.

Phys. Rev.

Thin Solid Films

Proc. Phys. Soc.

Phys. Rev.

Phys. Rev.

Japan J. Appl. Phys.

J. Appl. Phys.

J. Appl. Phys.

Reviews
Electronic properties of amorphous dielectric films