Structure and infrared reflectivity spectra of novel Mg3Ga2GeO8 microwave dielectric ceramic with high Q

Abstract

Mg3Ga2GeO8 ceramics were synthesised by means of the high-temperature solid-state reaction method. The Mg3Ga2GeO8 ceramics of the orthorhombic structure type comprised an Imma space group composed of three different octahedrons and one tetrahedron. The dense ceramic was obtained at 1340 °C and presented excellent microwave dielectric performances, namely, low εr = 9.41, high Q × f = 133, 113 GHz, and τf = −63.54 ppm/°C. The intrinsic microwave dielectric performances were analysed on the basis of the packing fraction, octahedron distortion, and infrared reflectivity spectra of the Mg3Ga2GeO8 ceramics. These merits render the Mg3Ga2GeO8 ceramics an appropriate candidate for millimetre-wave frequencies.