Traphyphen;modulated mobility of electrons and holes in Teflon FEP

摘要

The traphyphen;modulated mobilities of electrons and holes in 25hyphen;mgr;m Teflon FEP, charged by application of a high dc field at room temperature, are determined from thermally stimulated current (TSC) measurements performed under openhyphen;circuit conditions. Use of the TSC method allows one to evaluate approximately the effect of various trapping levels in the material (corresponding to different TSC peaks) on carrier mobility. For example, the first and second abovehyphen;roomhyphen;temperature TSC peaks for positive carriers yield mobilities of 10minus;11cm2/Vthinsp;sec at 50 and 80thinsp;deg;C, respectively. Similarly, for negative carriers, the second abovehyphen;roomhyphen;temperature TSC peak yields a mobility of 10minus;11cm2/Vthinsp;sec at 185thinsp;deg;C. The temperature dependence of the mobilities follows an Arrheniushyphen;type behavior with activation energies of 0.7 and 1.0 eV for the positivehyphen;carrier peaks and 1.8 eV for the negativehyphen;carrier peak.