Dielectric tunability of Ba0.6Sr0.4TiO3/poly(methyl methocrylate) composites in 1-3-type structure

The Ba0.6Sr0.4TiO3 (BST)/poly(methyl methacrylate) (PMMA) tunable composites in 1-3-type structure consisting of BST rods in low-permittivity PMMA matrix are fabricated by dice and fill technique. For the composite containing 41.6 vol % BST, the permittivity and the loss tangent of the composite are 1212 and 0.026 at 10 kHz, respectively, while the dielectric tunability is about 36% under the 16 kV/cm dc bias flied. The theoretical tunability and permittivity are in agreement with the experimental data. The 1-3-type BST/PMMA composites can meet the device requirement for tunable dielectrics with high dielectric tunability and low permittivity.