Microwave Dielectric Properties of Li2WO4 Ceramic with Ultra-Low Sintering Temperature

A new ultra‐low‐temperature firing microwave dielectric ceramic, Li2WO4 with the phenacite structure, was prepared via solid‐state reaction method. The Li2WO4 ceramic can be well sintered at 640°–660°C, with a microwave relative permittivity ∼5.5, a Q×f value about 62 000 GHz, and a negative temperature coefficient of −146 ppm/°C at 15.7 GHz. From an X‐ray diffraction analysis, the Li2WO4 ceramic was found to be chemically compatible with both silver and aluminum powders at 640°C. All the results indicate that the Li2WO4 ceramic is a promising candidate for ultra‐low temperature cofired ceramic technology, especially for dielectric substrate application.