Thickness-dependent properties of undoped and Mn-doped (001) PMN-29PT [Pb(Mg1/3Nb2/3)O3-29PbTiO3] single crystals

Abstract

In order to investigate the effect of thickness on the dielectric and piezoelectric properties of (001) PMN-29PT single crystals, three different types of PMN-29PT samples were prepared using the solid-state single crystal growth (SSCG) method: high density crystal [99%], low density crystal [95%], and high density crystal doped with Mn [98.5%]. When their thickness decreased from 0.5 mm to 0.05 mm, their dielectric constant (K3T), piezoelectric constants (d33 and g33), and electromechanical coupling factor (kt) decreased continuously. However, their dielectric loss (tan δ) increased. The addition of Mn to PMN-PT induced an internal bias electric field (EI), increased the coercive electric field (EC), and prevented local depoling. Therefore, Mn-doped PMN-PT crystals show high stability as well as high performance, even in the form of very thin plates (< 0.2 mm), and thus are suitable for application to high frequency composites, medical ultrasound probes, non-destructive testing devices (NDT), and flexible devices.