Transient photocurrents in UV-irradiated polytetrafluoroethylene coronoelectrets

It is experimentally found that UV irradiation of 10-m polytetrafluoroethylene films electrified in a negative corona discharge produces a transient current which is unipolar and whose peak value decreases in successive exposures. A model is considered on the basis of spatial impurity-center photoionization and the resultant positive-carrier motion, excluding recapture and recombination, in the strong internal field generated by trapped negative charges. Correlation of the experimental and calculated photocurrent kinetics yield values for the hole mobility (8.9×10^–15 m²·V^–1·sec^–1) and impurity-center concentration (1.5×10¹⁸ m^–3).Translated from Izvestiya Vysshikh Uchebnykh Zavedenii, Fizika, No. 6, pp. 26–29, June, 1990.