How to determine parameters of soft mode from dielectric spectroscopy performed using cells with ITO electrodes?

Abstract

Indium tin oxide (ITO) electrodes are widely used for liquid crystal applications as well as for measuring cells. Unfortunately, ITO layer possesses its own non zero resistivity R, which produces (with the cell capacity C0) the cut-off frequency f0 of RC0 circuit. From this reason, dielectric spectroscopy for high frequencies cannot be performed directly. The limits of classical method of extracting high frequency losses are shortly discussed. The new method of extracting high frequency losses is used for the first time for the experimental data. The new method can also evaluate the shrinkage of measuring cell gap after filling with liquid crystal. © 2011 Versita Warsaw and Springer-Verlag Wien.