Complex Permittivity Measurements at Variable Temperatures of Low Loss Dielectric Substrates Employing Split Post and Single Post Dielectric Resonators

TL;DR

This study compares split post and single post dielectric resonators for measuring the complex permittivity of various low-loss substrates across a range of temperatures, providing detailed resonator parameters and measurement conditions.

Contribution

It introduces and utilizes two types of dielectric resonators for temperature-dependent permittivity measurements of single crystal substrates, expanding measurement techniques.

Findings

Measured permittivity of substrates from 20 K to 300 K.

Resonant frequencies and Q-factors of resonators at 20 K.

Demonstrated effectiveness of resonators for low-temperature measurements.

Abstract

A split post dielectric resonator in a copper enclosure and a single post dielectric resonator in a cavity with superconducting end-plates have been constructed and used for the complex permittivity measurements of single crystal substrates. (La,Sr)(Al,Ta)O3, LaAlO3, MgO and quartz substrates have been measured at temperatures from 20 K to 300 K in the split post resonator and from 15 K to 80 K in the single post resonator. The TE01delta mode resonant frequencies and unloaded Qo-factors of the empty resonators at temperature of 20 K were: 9.952 GHz and 25,000 for the split post resonator and 10.808 GHz and 240,000 for the single post resonator respectively.