Influence and implications of surface contaminations on the charge decay in electrets

An investigation of the charge decay of Teflon FEP electrets at elevated temperatures showed considerable differences from sample to sample. Stronger charge decay for open stored samples suggest that surface contamination must have a significant influence on decay rate. For cleaning, distilled acetone was used. Cleaned sample had good reproducibility and a lower charge decay rate. Thermally stimulated charge decay measurements showed that cleaning shifts the charge decay into higher temperature ranges