Utilization of Photoconductive Gain in A-Si:H Devices for Radiation Detection


The photoconductive gain mechanism in a-Si:H was investigated in connection with applications to radiation detection. Various device types such as p-i-n, n-i-n and n-i-p-i-n structures were fabricated and tested. Photoconductive gain was measured in two time scales: one for short pulses of visible light (< 1 µsec) which simulates the transit of an energetic charged particle, and the other for rather long pulses of light (1 msec) which simulates x-ray exposure in medical imaging. We used two definitions of photoconductive gain: current gain and charge gain which is an integration of the current gain. We found typical charge gains of 3 ~ 9 for short pulses and a few hundred for long pulses at a dark current level of 10 mA/cm². Various gain results are discussed in terms of the device structure, applied bias and dark current.

Meeting Name

Proceedings of the 1995 MRS Spring Meeting


Nuclear Engineering and Radiation Science

Document Type

Article - Conference proceedings

Document Version


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© 1995 Cambridge University Press, All rights reserved.

Publication Date

01 Jan 1995