CC BY 4.0 UnportedFiedler, A.Schewski, R.Galazka, Z.Irmscher, K.2021-09-272021-09-272019https://oa.tib.eu/renate/handle/123456789/6914https://doi.org/10.34657/5961The relative static dielectric constant ℇr of β-Ga2O3 perpendicular to the planes (100), (010), and (001) is determined in the temperature range from 25 K to 500 K by measuring the AC capacitance of correspondingly oriented plate capacitor structures using test frequencies of up to 1 MHz. This allows a direct quantification of the static dielectric constant and a unique direction assignment of the obtained values. At room temperature, ℇr perpendicular to the planes (100), (010), and (001) amounts to 10.2 ± 0.2, 10.87 ± 0.08, and 12.4 ± 0.4, respectively, which clearly evidence the anisotropy expected for β-Ga2O3 due to its monoclinic crystal structure. An increase of ℇr by about 0.5 with increasing temperature from 25 K to 450 K was found for all orientations. Our ℇr data resolve the inconsistencies in the previously available literature data with regard to absolute values and their directional assignment and therefore provide a reliable basis for the simulation and design of devices. © The Author(s) 2019.enghttps://creativecommons.org/licenses/by/4.0/540620660Gallium compoundsAbsolute valuesCapacitor structuresIncreasing temperaturesMonoclinic crystal structurePrincipal planesStatic dielectric constantsTemperature rangeTest frequenciesCrystal structureArticle