Improved permittivity measurement of dielectric substrates by use of the TE111 mode of a split-cylinder cavity

Abstract

We use the split-cylinder cavity's TE111 resonant mode, in addition to the higher-order TE0np modes, to extend the frequency range over which one can nondestructively measure the permittivity of dielectric substrates. In addition to the frequency range of the split-cylinder resonator, we also demonstrate that measurements performed with the TE111 mode allow us to calculate the frequency of the higher-order TE0np resonant modes, thus reducing mode-identification errors. We compare relative permittivity measurements of several low-loss dielectric substrates using both the TE111 and the higher-order TE0np modes and employ the Monte Carlo method to calculate the measurement uncertainties.