The Study of the Photodielectric Effect in Zinc Sulphide Powder Doped with Copper and Chlorine

ABSTRACT

In this work we have tried to measure the photodielectric effect in ZnS (Cu, Cl) phosphor in two different steps². In the first step the capacitance C and the loss tan (δ) of a condenser containing a thin film of ZnS(Cu, Cl) powder as dielectric were determined as a function of frequency from 0·1 to 100 kc/s. at three temperatures T = 94°, 132° and 300°K. under ultraviolet illuminations of different intensity (wavelength 365 milli-microns). In the second step the capacity C and loss tan (δ) of this imperfect condenser were determined as a function of temperature T from 94° to 300°K. under ultraviolet illumination at three Hertzienne frequencies 0·2, 2 and 20 kc/s. These curves lead us to tell that the photodielectric effect in ZnS(Cu, Cl) is partly due to the phenomenon of photoconduction in the grain.