Thermal effects on polyimide electrical conductivity: experimental and numerical analysis

Abstract Kapton ® is a widely used material on spacecraft due to its excellent thermal and mechanical properties. Despite its widespread usage, the thermal dependence of its electrical properties remains a significant concern. An experimental investigation was conducted using the SIRENE facility (ONERA, Toulouse, France) in order to characterize the effect of temperature on the electrical behavior of Kapton ® . Through experimental evidence using a thermally stimulated current method, the trap distribution along the forbidden gap was highlighted. In addition, the existence of dark conductivity, unrelated to radiation exposure, was clearly identified. These physical mechanisms and characteristics were integrated into a numerical and physical conductivity model called THEMIS, which has been developed to assess charge transport in dielectrics in one dimension. The modified version of the THEMIS model was validated through experimental characterization. This work extends our understanding of charge transport in dielectric materials used in space, and suggests a validated method to model their behavior.