Ferroelectricity of Ce–Mn substituted ZnO thin films

Abstract

In this study, we introduced Ce and Mn as new substitution elements to develop ferroelectricity in wurtzite-type ZnO thin films on Pt/Ti/SiO2/Si. By substituting (Ce,Mn) for Zn, we observed a decrease in the c/a ratio, which reached its minimum value of 1.582. The relative permittivity increased from 12 to 20 with increasing (Ce,Mn) concentration (2%–15%), while the dielectric loss remained low at about 0.01. The Zn(Ce,Mn)O thin films exhibited clear ferroelectric behavior with a remanent polarization of more than 80 μC cm−2 and a coercive field of about 2.5 MV cm−1.