Dielectric barrier discharges in multi-layer polymer ferroelectrets

Cellular polymer foams with bipolar internal space charge are known as ferro - and piezoelectrets. Light emission from the internal voids of such polymer foams during electrical charging was already reported a few years ago and allows the investigation of the underlying dielectric barrier discharges. More recently, polymeric layer structures with well-defined voids were presented as an alternative to polymer-foam ferroelectrets. The simpler and more uniform voids in layered ferroelectrets are more suitable as model systems for dielectric barrier discharges across a single gap between two polymer layers and two external electrodes. In this contribution, we report and discuss first results from electrical and optical experiments and propose a theoretical explanation for the internal charging process (including eventual back discharges) in simple multi-layer ferroelectrets.