Residual stress and interface effect on dielectric mechanisms in poled ultrathin relaxor ferroelectric single crystals

Abstract

We have investigated the dielectric performances and mechanism of super-thin Mn-doped Pb(Mg1/3Nb2/3)O3-PbTiO 3 crystals, exhibiting significantly different dielectric behaviors compared with thick wafer. Dramatic decrease by 5 times and large frequency dispersion of permittivity, changed diffuse degree of phase transition, dielectric loss anomaly with frequency and dielectric performances with direct-current electric field for thin wafers are observed, proving the existence of large surface residual stress and interface effects. Additionally, a theoretical model of low-permittivity and low-ferroelectric surface damage layers is concurrently proposed. These observations have important implications for actual performances of thin wafers applied in practical devices. © 2014 AIP Publishing LLC.