A new type of dielectric composite with X7R characteristic and high dielectric constant

A new dielectric composite for capacitors, with a high dielectric constant in excess of 9000 at 25 degreesC and low-sintering temperature, has been su ccessfully developed by sintering layer-like-structure green body made up o f four types of calcined ph-based complex perovskite with different Curie t emperatures. It can well satisfy the X7R EIA specification, Dielectric meas urements showed that the as-sintered layer-like dielectric is a multiphasic ceramic composite. The flat dielectric-temperature characteristic was cons idered to come from the macroscopical inhomogeneity. The effects of stackin g order on the dielectric properties of the composite were found. An optimu m stacking procedure was identified. (C) 2001 Elsevier Science B.V. All rig hts reserved.