金属-ポリイミドLB膜界面の帯電とその温度•光特性

抄録

Surface potential of heat-treated polyimide (PI) LB films deposited on Au, Cr, Al and ITO electrodes was measured in a dark vacuum vessel at various temperatures before and after photoirradiation. The surface potential depended on the electrode materials and the number of deposited layers. The surface potential saturated when the number of deposited layers was several tens. The saturated surface potential was a linear function of the work function of electrodes at temperatures between-100°C and 150°C before photoirradiation, and at room temperature after photoillumination. It was suggested that excess charges were transferred from metal-electrodes into PI LB films until the thermodynamic equilibrium was established at the interface. We also measured the surface potential of 4kinds of polyimide LB films. The potential of polyimide with electron accepters changed negatively, and the potential of polyimide with electron donors changed positively with the increment of temperature. In contrast, the potential of polyimide with electron accepters changed positively, and the potential of polyimide with electron donors changed negatively with photoirradiation.