Production and characterisation of composite relaxor ferroelectric multi-layer structures

The drive for miniaturisation of passive capacitor and filter devices requi res dielectric materials with higher relative permittivities than can be at tained using normal ferroelectrics. Relaxer ferroelectrics possess the requ ired high relative permittivities hut are incapable of being chemically dop ed to give a temperature stable capacitance. Work is presented detailing th e design and development of a new class of temperature stable high volumetr ic efficiency multi-layer capacitors. Various compositions of high relative permittivity relaxer ferroelectrics are consintered in to a multi-layer ca pacitor with controllable temperature characteristics. The materials used a re all doped perovskite Pb(Mg1/3Nb2/3)O-3 (PMN) compositions. The ceramic p owder-processing route required to make such structures is summarised with reference to the unique device fabrication problems encountered. Dielectric measurements of the prototype devices are presented. (C) 1999 Elsevier Sci ence Limited All rights reserved.