TEMPERATURE DEPENDENCE OF THE MICROWAVE DIELECTRIC CONSTANT OF THE GaAs LATTICE

Abstract

The relative dielectric constant ε_r of high‐resistivity GaAs has been measured at 70.243 GHz as a function of temperature between 100 and 300°K. The measuring technique utilized a circular E field ${\mathrm{(TE°}}_{01})$ mode reflection‐coefficient bridge. Estimated relative and absolute accuracies of the measurements are ±0.2% and ±0.5%, respectively. The results are found to fit the equation ε_r(T) = ε_r(0){1 + αT} where ε_r(0) = 12.73 ±.07 and α = (1.2 ± 0.1) × 10⁻⁴. At room temperature (295°K) the relative permittivity is ε_r = 13.18 ±.07.