Contact free potential mapping by vibrating capacitor

The contact free vibrating capacitor method is a valuable tool for investigating the surface potentials of solid surfaces. The purpose of the present article is to summarize the theory and capabilities of the vibrating capacitor method, especially scanning vibrating capacitor pictures in the electronics. After a brief review some results will be discussed, such as a contact potential map taken from a printed circuit board, a surface potential map from a biased ceramic thick film circuit and some results from silicon solid state devices and solar cells. Potential maps contain a lot of information concerning the surface conditions, included the inhomogeneities of the technology, bias and other additional excitation. These potential maps may help in the development, quality control and defect analysis