Improved piezoelectric performance via orientation regulation in novel BNT-BT-SBT thin film

Lead-free piezoelectric thin films are urgently needed in microelectronic and microelectromechanical systems. In this work, (1- x )(0.94Bi 0.5 Na 0.5 TiO 3 -0.06BaTiO 3 )- x (Sr 0.7 Bi 0.2 □ 0.1 )TiO 3 (abbreviated as BNT-BT- x SBT) piezoelectric thin films were prepared successfully. The optimal piezoelectric performance can be achieved when x = 0.02 at morphotropic phase boundary (MPB). Further, to explore the impacts of orientation control on the properties of thin films, (100), (110), and (111)-oriented BNT-BT-0.02SBT thin films were prepared on Nb-SrTiO 3 single crystal. The (110) preferred orientation thin film can achieve a high inverse piezoelectric coefficient ( d 33 ⁎ ) of 170 pm/V, which has a great improvement contrasted with non-oriented films. From the perspective of engineering domain configuration, the high d 33 ⁎ of (110)-oriented thin film can be characterized that the ferroelectric domain can get a complete flip in the direction of non-easily polarized axes. In short, orientation regulation is of great importance in improving the piezoelectric properties of thin films and has important applications in microelectronic sensing. • BNT-BT- x SBT ternary thin films at MPB were prepared by sol-gel method. • (100), (110) and (111)-oriented thin films were prepared on Nb-SrTiO 3 single crystal. • Grain growth can be promoted along with the densely stacking plane orientation. • (110)-oriented thin film obtains the optimal inverse piezoelectric coefficient (170 pm/V). • The ferroelectric domain get complete flip in the direction of non-easily polarized axes.