title: Thickness Dependent Properties of Relaxor-PbTiO(3) Ferroelectrics for Ultrasonic Transducers.
abstract: The electrical properties of Pb(Mg(1/3)Nb(2/3))O(3)-PbTiO(3) (PMN-PT) based polycrystalline ceramics and single crystals were investigated as a function of scale ranging from 500 microns to 30 microns. Fine-grained PMN-PT ceramics exhibited comparable dielectric and piezoelectric properties to their coarse-grained counterpart in the low frequency range (<10 MHz), but offered greater mechanical strength and improved property stability with decreasing thickness, corresponding to higher operating frequencies (>40 MHz). For PMN-PT single crystals, however, the dielectric and electromechanical properties degraded with decreasing thickness, while ternary Pb(In(1/2)Nb(1/2))O(3)-Pb(Mg(1/3)Nb(2/3))O(3)-PbTiO(3) (PIN-PMN-PT) exhibited minimal size dependent behavior. The origin of property degradation of PMN-PT crystals was further studied by investigating the dielectric permittivity at high temperatures, and domain observations using optical polarized light microscopy. The results demonstrated that the thickness dependent properties of relaxor-PT ferroelectrics are closely related to the domain size with respect to the associated macroscopic scale of the samples.
authors.affiliation: Materials Research Institute, Department of Materials Science & Engineering, The Pennsylvania State University, University Park, PA, 16802 (USA).
authors.forename: Hyeong Jae
authors.initials: HJ
authors.lastname: Lee
authors.forename: Shujun
authors.initials: S
authors.lastname: Zhang
authors.forename: Jun
authors.initials: J
authors.lastname: Luo
authors.forename: Fei
authors.initials: F
authors.lastname: Li
authors.forename: Thomas R
authors.initials: TR
authors.lastname: Shrout