Microfocus-infrared synchrotron ellipsometer for mapping of ultra thin films

A purpose-build infrared spectroscopic ellipsometer is presented that enables to investigate sample areas of less than 1 mm2 with monolayer sensitivity. This sensitivity is achieved for films on metallic as well as on semiconducting substrates. Measurement principle and performance of the instrument are discussed on selected examples and an outline of the currently performed upgrading of the set-up is given.