Translator Disclaimer
8 May 2007 Measurement of thin films using slightly dispersive spectral interferometry
Author Affiliations +
We present a white-light spectral interferometric technique which is used for measuring the absolute spectral optical path difference (OPD) between the beams in a slightly dispersive Michelson interferometer with a thin- film structure as a mirror. Two spectral interferograms are recorded to obtain the spectral interference signal from which the spectral phase is retrieved that includes the effect of both a cube beam splitter and the phase change on reflection from the thin-film structure. Knowing the effective thickness and dispersion of the beam splitter made of BK7 optical glass, a simple procedure is used to determine both the absolute spectral phase difference and OPD. The spectral OPD is measured for a SiO2 thin film on a silicon substrate and is fitted to the theoretical spectral OPD to obtain the thin-film thickness. The theoretical spectral OPD is determined provided that the optical constants of the thin-film structure are known. We measured also the nonlinear-like spectral phase and fitted it to the theoretical values in order to obtain the thin-film thickness.
© (2007) COPYRIGHT Society of Photo-Optical Instrumentation Engineers (SPIE). Downloading of the abstract is permitted for personal use only.
R. Chlebus, P. Hlubina, D. Ciprian, and J. Lunacek "Measurement of thin films using slightly dispersive spectral interferometry", Proc. SPIE 6582, Nonlinear Optics and Applications II, 65821D (8 May 2007);

Back to Top