Improvement of piezoelectric properties of relaxor type 0.695Pb(Mg1/3Nb2/3)O3−0.305 PbTiO3 single crystal plate and silver vibrator by alternating current poling

Abstract

Abstract Alternating current poling (ACP) and direct current poling (DCP) on [001]-oriented 0.695Pb(Mg1/3Nb2/3)O3−0.305PbTiO3 (PMN-0.305PT) single crystal (SC) plates with a dimension of 12 × 4 × 0.3 mm and silver vibrators of 12 × 0.15 × 0.3 mm were investigated. The highest dielectric constant of 14500 and piezoelectric constant of 4200 pCN−1 were confirmed with the ACP SC plate manufactured by the conventional one charge Bridgman process. After array dicing into silver, the silver mode coupling coefficient k’ 33 = 94.3% was obtained from ACP SC. However, many spurious mode vibrations (SMV) were seen in the impedance spectra of the DCP and ACP SC silver vibrators. We consider that this SMV may be caused by array dicing damage. The PMN-0.305PT SC plate near the morphotropic phase boundary shows excellent piezoelectric and dielectric properties, however, these silvers tend to show SMV after dicing. This information is useful to select the PMN-PT composition for medical probe application.