Effects of Electrode on Space Charge Properties of Polyimide Films

Space charge formation in polyimide films, and therefore, charge injection from the electrodes largely depend upon the water content. In order to clarify the injection properties of positive and negative charge carriers, space charge distributions were observed in the polyimide films with different electrode conditions, such as aluminium was evaporated on a surface of the samples. Only when the rear electrode is a semi-conductive material, the evaporated aluminum electrode enhances charge injection. The positive and negative charge carriers had similar electrode effects on injection each other