Processing and Dielectric Properties of TiO_2 Thick Films for High-Energy Density Capacitor Applications

摘要

Nanosized titanium dioxide (TiO_2) powders (～ 40 nm) were used for preparation of tape-casting slurries. Effect of various solvents and dispersants on the dispersability of TiO_2 slurries was studied by sedimentation tests and rheology measurements. TiO_2 green tapes were prepared by tape-casting method and densified at 1000°C with a sintered density >95%. Dielectric properties of TiO_2 tapes were studied by measuring of dielectric constant, loss factor and dielectric breakdown strength (BDS) with respect to their microstructural development. BDS values as high as ～ l400kV/cm were obtained for sintered tapes so that energy densities up to l4J/cm~3 could be achieved.