Microstructure and dielectric properties of barium strontium titanate thick films and ceramics with a concrete-like structure

Barium strontium titanate (Ba0.6Sr0.4TiO3, BST) thick films and ceramics with a concrete-like structure were fabricated by a novel sol-gel-based route. In this process, well-crystallized nanosized or micrometer-sized BST powders or their combinations are dispersed into a sol-gel matrix. Crack-free thick films and dense BST ceramics have been fabricated at a low sintering temperature with a very inhomogeneous concrete-like structure. The dielectric properties of such thick films and ceramics have been investigated. The results show that the dielectric constant and loss tangent of the thick films are 1209 and 0.016, respectively, at 0 degrees C, 10 kHz, and those of the bulk BST ceramics are 5510 and 0.02, respectively, at 0 degrees C, 10 kHz.