Mobile fluoride ions in SiO2

Abstract
We have obtained evidence that fluoride ions are mobile in SiO2 at room temperature. The outer surface of a thin layer of the oxide is coated with a fluoride salt and charged by a negative corona discharge in air. From shifts in the CV curve and changes in the properties of trapping states near the interface we infer that negative ions have moved through the oxide. This is confirmed by an analysis with a secondary−ion mass spectrometer.