Quantitative ellipsometric microscopy at the glass-water interface

Abstract

Ellipsometric microscopy is a technique for simultaneous measurement of thin film thickness and index of refraction at a lateral resolution of approximately 1 μm. Up to now this technique has been used on silicon-air interfaces. However, biological processes take place often in aqueous solution and are studied at the glass-water interface. Due to the very low reflectivity of this interface we had to improve ellipsometric microscopy substantially. Here we present our approach to suppress the intensity of internal stray light by several orders of magnitude and show quantitative and laterally resolved ellipsometric measurements at the glass-water interface. When instrumental polarization was taken into account, an accuracy of δψ = 0.41° and δΔ = 4.3° was achieved. © IOP Publishing Ltd and Deutsche Physikalische Gesellschaft.