Influence of the electrode material in a metal-polymer-metal structure on the temperature dependence of the thermally stimulated current

The dependences of the thermally stimulated current in metal-polymer-metal structures with electrodes prepared from different materials are investigated. Poly(diphenylenephthalide) films are used as a polymer. The possible contribution of the injection component to the thermally stimulated current spectrum is considered. The injection conditions are changed by replacing the electrode material. It is established that the change in the material does not lead to a change in a qualitative behavior of the temperature dependence of the current. However, the use of copper as the electrode material gives rise to an additional injection component in the thermally stimulated current spectrum and (under specific conditions) electronic switching of the sample from an insulating state to a highly conducting state. The charge is injected into deep localized electronic states that lie near the middle of the band gap of the polymer.