A textured barium niobate with enhanced temperature stability of dielectric constant for high-frequency applications

Ba5Nb4O15 has shown excellent microwave dielectric properties and is under consideration as a low-temperature cofired ceramic material for advanced radio frequency (RF) applications. By combining tape casting and liquid phase upon sintering, sintered Ba5Nb4O15 thick films stacked to form laminates were produced with aligned elongated grains. This texture engineering, correlated with crystallographic orientation, provides remarkably high temperature stability of dielectric constant up to microwave frequency. Crystallographic texture arises in Ba5Nb4O15 induced by the primary consolidation process, hot pressing, and pulsed laser deposition. The dielectric anisotropy could be efficiently obtained in the textured samples, thereby enabling significant feasibility of microwave circuit designs.