Determination of charge centroid in thin films by corona-charging and TSD techniques

A new method to determine the charge centroid in thin films is proposed, based on corona charging and thermally stimulated discharge (TSD) techniques as well as surface potential measurement. The method consists in superimposing the opposite polarity charge and thereafter subjecting the sample to TSD. The surface potential varies with charge detrapping and neutralization. The original charge centroid can be derived from these parameters under the assumption that the activation energies are different for positive and negative carriers and the origin charge has higher activation energy. Both theoretical analysis and experimental results are given.