Thermally stimulated currents of corona treated Teflon-FEP electrets

Abstract

Thermally stimulated currents of corona-charged Teflon FEP electrets show a single peak around 210 degrees C short polarization times. However, when the polarization time or the corona current is increased, changes either in the maximum or in the position of the peak occur. At the same time a broad current band in the range between 100-180 degrees C appears, while a liquid is formed over the electret surface. Measurements of the charged centroid show no detectable change in the location. The results are tentatively explained in terms of surface traps becoming shallower.<>