Determination of thickness and dielectric constant of coatings from capacitance measurements

We presented a proof of principle experiment in which we obtained a few points along a few curves of constant h and variable h for a stripped and spherical electrode. We used liquid films in a planar cell made of a glass slide on top of a copper plate to obtain calibration curves. The glass slide was considered part of the electrodes. We could show that the curves are clearly separated in the capacitance space. By using eight experimental capacitance points belonging to four constant thickness curves it was possible to estimate the thickness of a glass slab with a reasonable error. The results presented here can certainly be improved, but we believe they are sufficient to demonstrate the viability of the method. © IEEE 2007.