Radiation-induced conductivity in electron-beam irradiated insulating polymer films

The radiation-induced conductivity (RIC) in polypropylene, polyethylene terephthalate, and polyimide due to electron-beam irradiation is measured with an external bias method and, in the case of polypropylene, also with a short-circuit method, as a function of dose rate and time of irradiation or total dose. The results substantiate the power-law dependence of the RIC on dose rate in all cases, but indicate that the dependence on time is different for the materials under investigation. In addition, the delayed radiation-induced conductivity (DRIC) is determined. The DRIC shows a hyperbolic time dependence with different exponents for the different materials