Low temperature co-fired ceramics with ultra-low sintering temperature: A review

Abstract

The recent rapid advances in wireless telecommunication, Internet of Things, the Tactile Internet (5th generation wireless systems), the Industrial Internet, electronic warfare, satellite broadcasting, and intelligent transport systems demand low loss dielectric materials with ultra-low sintering temperatures with modern component fabrication techniques. Properties of microwave ceramics depend on several parameters including their composition, the purity of starting materials, processing conditions, and their ultimate densification/porosity. The preparation, characterization and properties of important materials families such as glass ceramics and molybdates, tellurates, tungstates and vanadates, in combination with Bi, K, Na, Ag, Li, Ba, Ca, etc. with ultra-low sintering temperatures are discussed. In this review the data for all reported low-loss microwave dielectric ceramic materials with ultra-low sintering temperatures are collected and tabulated. The table of these materials gives the relative permittivity, quality factor (tanδ), temperature variation of the resonant frequency, crystal structure, sintering temperature, measurement frequency and references. The data arranged in the order of increasing relative permittivity will be very useful for scientists, industrialists, engineers and students working on current and emerging applications of microelectronics.