A. Tabata et al., Electrical properties before and after light-soaking of hydrogenated amorphous silicon carbide films prepared by the hydrogen radical CVD method, J PHYS D, 32(18), 1999, pp. 2448-2453
Hydrogenated amorphous silicon carbide (a-Si1-xCx:H) films were prepared by
use of the preparation system possessing a hydrogen plasma chamber and a s
ilane/methane plasma chamber (the hydrogen radical chemical vapour deposit
(CVD) method) and their electrical properties before and after light-soakin
g were investigated. The photo- and dark conductivities both before and aft
er light-soaking increased with increasing rf power on the hydrogen plasma
side; however, the photosensitivity remained unchanged. The activation ener
gy of the dark conductivity before light-soaking decreased with increasing
rf power on the hydrogen plasma side, while that after light-soaking increa
sed. The defect density decreased with increasing rf power on the hydrogen
plasma side. The hydrogen radical CVD method was found to be useful for pre
paring a-Si1-xCx:H films with high photoconductivity and low defect density
. The electrical properties obtained in this study were explained by the tw
o-energy-level model. Although the hydrogen radical CVD method mainly reduc
ed the defect density of the lower energy level, it also reduced that of th
e upper energy level.