Simulation of surface potential decay of corona char ged polyimide

Surface potential decay (SPD) of corona charged polyimide (PI) films has been studied using different initial potentials Vo. It has been noticed that the rate of decay increases with initial charging levels. Surface potential profile over the surface of the PI films and return potential generated after charge neutralization have been also experimentally recorded. In order to analyse and explain the decay behavior, the recorded SPD in PI film has been computer simulated using a numerical model based on charge transport by hopping of injected carriers between localized trapping centers. Three parameters (transit time tT, trapping time τTand mean capture time before release τF) controlling the decay kinetic have been estimated by fitting procedure. The effects of the electric field strength on the transport parameters have been also discussed.