Differential charging in X-ray photoelectron spectroscopy for characterizing organic thin films

Differential charging of non-uniformly conducting samples in X-ray photoelectron spectroscopy studies leads to the distortion of emission peaks and shifts in the measured positions of peaks. By using static sample biasing, these nuisance effects can be taken advantage of, in order to extract useful information about the sample. This article reviews the use of this static sample biasing method to distinguish between monolayer and multilayer organic films on oxidized silicon substrates, for the determination of the thickness of deposited organic layers, and to distinguish laterally uniform from laterally non-uniform films on stainless steel samples.