| Numéro |
J. Phys. Colloques
Volume 42, Numéro C4, Octobre 1981
Proceedings of the Ninth International Conference on Amorphous and Liquid Semiconductors
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|---|---|---|
| Page(s) | C4-563 - C4-566 | |
| DOI | https://doi.org/10.1051/jphyscol:19814122 | |
J. Phys. Colloques 42 (1981) C4-563-C4-566
DOI: 10.1051/jphyscol:19814122
TRANSIENT PHOTOCONDUCTIVITY AND SCHOTTKY BARRIER PROFILE DETERMINATION IN a-Si:H
T. Datta and M. SilverPhysics and Astronomy Department, University of North Carolina, at Chapel Hill, North Carolina, 27514, U.S.A.
Abstract
Carrier drift studies on submicron thick a-Si alloys sandwiched between blocking metal and injecting contacts reveal anomalous behavior. Using a pulsed external field and a tuneable-pulsed, nano-second laser, we observe that the transient photo current cannot be explained by the current response of a sheet of drifting charges. The non drift contributions appear to originate from the time dependent relaxation of the Schottky barrier as a result of the photo excitation. This effect is more obvious in the small forward bias (≤+1.0 volts) mode, when a reversal of the photo response is obtained. Also, we have devised a novel technique to determine the junction potential profile. This is done by measuring the external field required to null the initial photo current as a function of the excitation wave length (hence, the penetration depth).