Impedance spectroscopy in micro systems

Abstract Impedance spectroscopy in a potentiostatic three-electrode configuration is extended to spatially resolved surface analysis with a resolution of about 10 μm, which is interesting for very many technical systems. Dot-by-dot experiments or complete surface scans to yield impedance images are presented. Examples of technical applications are the investigation of defects in CrN x hard coatings on Mg alloys, the grain dependent passivation of polycrystalline metals, and structuring of ultrathin Al films.