Raman line-shape analysis of nano-structural evolution in cation-ordered ZrTiO4-based dielectrics

It is known that the microwave dielectric characteristics of ZrTiO4 are greatly influenced by processing conditions such as the degree of Sn-modification and the cooling rate after sintering. The effects of these processing variables on the nano-structural characteristics of ZrTiO4-based dielectrics were studied by analyzing the Raman line-shape parameters using the phonon-confinement model. It was shown that the nano-structural shape of the cation-ordered domains underwent a sequential change from thin-slab form to platelet shape, and finally to spherical shape with increasing Sn-content or cooling rate.