Krause, CorinnaBergmann, Ralf B.Falldorf, Claas2025-05-062025-05-062022-03-082196-7113https://media.suub.uni-bremen.de/handle/elib/8950https://doi.org/10.26092/elib/3829To determine step heights between a few nanometers and several micrometers, we present a statistical evaluation procedure which overcomes the limitations of the unambiguity range of conventional multi-wavelength interferometry. The experimental setup consists of a shear interferometer with two different wavelengths to measure the phase difference between light reflected from an object with regions of two different heights. The statistical averaging over a large area of both regions of the object for both wavelengths generates a pair of phase difference values. A diagram of the space of phase values converts the pair of phase difference values into a step height. This statistical method enables the determination of step heights greater than the synthetic wavelength with an accuracy of a few nanometers even with small tilts of the object.enCC BY-NC-ND 4.0 (Attribution-NonCommercial-NoDerivatives)https://creativecommons.org/licenses/by-nc-nd/4.0/Interferometrymulti-wavelengthshear interferometrystep measurementstatistical analysis method600Artikel/Aufsatz10.26092/elib/3829urn:nbn:de:gbv:46-elib89501