Determination of thickness and refractive index of thin films (PDF file, 188 KB)
Ellipsometry measures variations of the polarization state of light reflected from a surface. Optical constants (n and k) of the substrates and layers as well as layer thickness can be determined. In our lab spectroscopic and imaging ellipsometry in the visible spectral range are used to characterize thin organic layers (mainly polymers) on solid substrates. In focus are in-situ measurements in air/N2 and liquids (as function of time, temperature, composition, pH..), e.g. swelling/deswelling, adsorption/desorption, thermal expansion….