Effects of a corona discharge on the charge stability of Teflon FEP negative electrets

Abstract

Measurements of TSD together with surface potential were used to study negative corona discharge effects on the charge stability of Teflon FEP electrets. During charging, liquid formation over the sample surface (clearly visible for long-time corona irradiation) was concluded to be responsible for a decreasing in the thermal charge stability. The authors also discuss the charge stability at room temperature, while the sample is exposed to the neutral activated species from a corona discharge source. A decay in the potential was observed and this was attributed to a surface charge compensation by positive ions, and not to neutral activated molecules coming from the corona tip as suggested previously.