Direct Piezoelectric Properties of Mn-Doped ZnO Epitaxial Films

Abstract

The direct piezoelectric properties of Mn-doped ZnO epitaxial films prepared by pulse laser deposition was investigated. The resistivity of the ZnO films was markedly decreased by Mn doping. The effective transverse piezoelectric coefficient ( e 31, f ) of the ZnO films was measured by substrate bending and collecting developed charges. The dependence of induced charge density on applied strain indicates that the obtained piezoelectric response originates from the spontaneous polarization of the Mn-doped ZnO films. The e 31, f values of 3 and 5 at. % Mn-doped ZnO films were determined to be -1.09 and -1.10 C/m 2 , respectively, which are comparable to the theoretical value.