New approach of measuring the Q factor of a microwave cavity using the cavity perturbation technique

Abstract

A new approach of measuring the quality factor of the reflection type microwave cavity resonator for calculating the complex dielectric permittivity of solid and liquid samples in the cavity perturbation technique is proposed. This approach, based on the measurement of reflected power from the cavity at resonance, effectively reduces the measurement procedure and increases the accuracy. As the quality factor can be measured very fast using this approach, this approach can be extended to monitor the conductivity decay of the semiconductor samples.

Contactless thermally stimulated lifetime measurements in detector-grade cadmium zinc telluride

“…[9][10][11] The change in the quality factor and/or resonant frequency of the microwave cavity upon photoexcitation of the semiconductor sample is the basis for the technique. The dielectric loss (⑀Љ) is proportional to the material conductivity and can be expressed as…”

“…11 Thus, the effective carrier lifetime can be obtained directly by observing the decay of the reflected microwave signal after the removal of the excitation source. The measurement sensitivity is known to depend on a variety of parameters including the quality factor, the sample size, and the cavity coupling factor.…”