Method and apparatus for characterising multilayer thin film systems and for measuring the distance between two surfaces in the presence of thin films

摘要

A method and apparatus are disclosed for characterising a one or more layer thin film system on a substrate, in particular in respect of layer thickness and refractive index, and for measuring the distance between two surfaces, wherein at least one of the surfaces comprises a one- or multi-layer system, taking into account, and allowing rectification of, the phase contribution from the thin film stack, by interferometry, in particular by white-light channelled spectrum interferometry or multi-wavelength interferometry.