Investigation of Photoconductivity in Cadmium Sulfide
No Thumbnail Available
Date
1984-06
Authors
Journal Title
Journal ISSN
Volume Title
Publisher
Addis Ababa University
Abstract
In this thesis the photoconductivity of polycrystalline
cadmium sulfide was investigated theoretically and experimentally.
The theory shows that both a change in carrier conent~
ration and mobility can contribute to the variation in conduc~"
tivity under illumination depending on the doping level, trap
concentration and light intensity. Thin-film polycrystalline
layers of CdS were prepared by the chemical bath deposition
technique. Doping with lithium was possible. X-ray investigation
of the layers indicated that the layers are made up of
very small crystallites. Annealing enhanced recrystallization
increasing the crystallite dimension.
Besides polycrystalline CdS, monocrystalline and pressed
CdS were used for photoconductivity measurements. The annealed
layers showed a spectral photoresponse similar to the monocrystalline
CdS with an absorption edge at 2.4e'1. In order to
measure the lifetime of the charge carriers, the photoconductive
decay process was used. The lifetime was found to have a
spectral dependence
Description
Keywords
Investigation of Photoconductivity