Published online by Cambridge University Press: 15 February 2011
The structures of all the prominent ceramic dielectric resonators have been found to exhibit extensive inhomogeneity. This structural disorder arises from the formation of extended defects, polytype intergrowths or variable degrees of cation order. For the systems involving a cation order-disorder reaction, e.g. ZrTiO4 and Ba(Zn1/3Ta2/3)O3, the formation of internal interfaces can have a pronounced effect on the dielectric properties. In the absence of secondary dopants the lattice strains associated with the interfaces increase the dielectric losses by as much as two orders of magnitude. However, the contributions of the interfaces can apparently be controlled, and perhaps eliminated, by introducing selected dopants that segregate and stabilize the local boundary regions.