The formation of deep traps in the near surface layers of fluoropolymer corona electrets

Abstract

Summary form only given, as follows. The stability of a positive homocharge in nonpolar fluoropolymer corona electrets is due to the polymer surface states. Electret stability can be controlled by changing the trapping-level spectrum in the thin, near-surface dielectric layers. The methods of formation of deep traps in fluoropolymer dielectrics before polarization and in the process of the electret state formation are considered. It is shown that the formation of deep traps for the positive homocharge in fluoropolymer dielectrics essentially depends on the duration of the adsorption process. The fraction of deep traps in the surface-state spectrum increases with duration of treatment. This process is considerably intensified during the treatment of films initially charged by positive homocharge or during triboactivation of surface in the process of treatment. On the basis of the model conceptions the energy spectrum of near-surface trap layers of polymer is determined, and the correlation of the spectrum with the surface structure is established. >