Microwave/Terahertz Dielectric Properties of a Novel NaSrGdMo 3 O 12 Scheelite Ceramic for Patch Antenna Applications

ABSTRACT The development of high‐performance dielectric ceramics for LTCC substrates is essential for next‐generation communication systems. In this study, a novel NaSrGdMo 3 O 12 ceramic was synthesized, which achieved densification at 875°C and exhibited excellent microwave dielectric properties ( ε r = 10.34, Q × f = 31 988 GHz, and τ f = −33.96 ppm/°C). The ceramic crystallized in a tetragonal scheelite‐type structure. An optical bandgap of 4.12 eV was determined, and the electrical relaxation mechanisms were analyzed using complex impedance spectroscopy. Furthermore, the lattice vibrational characteristics were investigated through FTIR spectroscopy. Analysis based on the P–V–L theory established a direct structure–property relationship, revealing that Na/Sr/Gd─O bonds dominate the permittivity, whereas Mo─O bonds control the quality factor and thermal stability. The material also exhibited low dielectric loss in the terahertz frequency range. A functional Sub‐6G patch antenna was fabricated to validate its practical applicability.