| Issue |
J. Phys. Colloques
Volume 42, Number C4, Octobre 1981
Proceedings of the Ninth International Conference on Amorphous and Liquid Semiconductors
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|---|---|---|
| Page(s) | C4-127 - C4-131 | |
| DOI | https://doi.org/10.1051/jphyscol:1981424 | |
Proceedings of the Ninth International Conference on Amorphous and Liquid Semiconductors
J. Phys. Colloques 42 (1981) C4-127-C4-131
DOI: 10.1051/jphyscol:1981424
Technische Universität München, D 8046 Garching, F. R. G.
J. Phys. Colloques 42 (1981) C4-127-C4-131
DOI: 10.1051/jphyscol:1981424
THEORY OF DISPERSIVE TRANSPORT IN AMORPHOUS SEMICONDUCTORS
K. Godzik and W. SchirmacherTechnische Universität München, D 8046 Garching, F. R. G.
Abstract
We present a theory of dispersive drift transport in amorphous photoconductors. Expressions for the transient current i (t) are derived from the two-site effective medium approximation (EMA) which is equivalent to a generalized master equation approach. The occurrence of Gaussian or dispersive transport is shown to depend on an interplay of three characteristic time constants. Explicit expressions for these time constants are given in terms of microscopic parameters. We show that dispersive transport in hopping systems can only exist for very small times and densities. Experimental findings can be much easier explained within a trapping model which is solved by means of the CPA.