Microwave Dielectric Properties of Li ₂ WO ₄ Ceramic with Ultra‐Low Sintering Temperature

Abstract

A new ultra‐low‐temperature firing microwave dielectric ceramic, Li 2 WO 4 with the phenacite structure, was prepared via solid‐state reaction method. The Li 2 WO 4 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 Li 2 WO 4 ceramic was found to be chemically compatible with both silver and aluminum powders at 640°C. All the results indicate that the Li 2 WO 4 ceramic is a promising candidate for ultra‐low temperature cofired ceramic technology, especially for dielectric substrate application.