Effect of argon dilution of silane on persistent photoconductivity in single-layered hydrogenated amorphous silicon

The effect of argon dilution of silane on the persistent photoconductivity (PPC) has been studied for single-layered hydrogenated amorphous silicon films prepared by a glow-discharge decomposition. The magnitude of the PPC effect and the columnar-growth morphology increase when the argon-to-silane mixing ratio increases to 10. Above this ratio both the PPC and the columnar pattern decrease. A clear correlation between the magnitude of the PPC and the microstructure has been observed for undoped single-layered films. It is concluded that the PPC effect is not confined to the multilayers and to the compensated films, and that by increasing the microstructure in undoped films through argon dilution the effect can be increased.