A novel NaMg(1-)Zn (PO3)3 microwave dielectric ceramic with an ultra-low dielectric constant for LTCC application

In millimeter-wave communication, signal delay becomes increasingly pronounced as the operating frequency of the equipment rises. To accelerate signal transmission, substrates with low dielectric constants (εr < 6) are required. This study synthesized a novel microwave dielectric material, NaMg(1-x)Znx(PO3)3 (NMZPO), using the conventional solid-phase method. The microwave dielectric properties of NaMg(PO3)3 ceramics were enhanced by substituting Mg2+ with Zn2+. Specifically, Zn2+ doping increased the ceramics' densification and reduced dielectric loss. The NaMg0.9625Zn0.0375(PO3)3 ceramic exhibited optimal microwave dielectric properties at sintering temperature 880 °C for 4h: εr = 4.49, Q × f = 58237.2 GHz (at 17.792 GHz), τf = −50.6 ppm/°C. In addition, NMZPO ceramics demonstrate excellent chemical compatibility with Ag electrodes. These findings indicate that NMZPO represents a promising candidate for the next generation of ultra-low dielectric constant LTCC materials.