Dielectric properties of c-axis oriented Zn_1-xMg_xO thin films grown by multimagnetron sputtering

Abstract

Zn_1-xMg_xO (x = 0.3) thin films have been fabricated on Pt/TiO₂/SiO₂/Si substrates using multimagnetron sputtering technique. The films with wurtzite structure showed a (002) preferred orientation. Ferroelectricity in Zn_1-xMg_xO films was established from the temperature dependent dielectric constant and the polarization hysteresis loop. The temperature dependent study of dielectric constant at different frequencies exhibited a dielectric anomaly at 110° C. The resistivity versus temperature characteristics showed an anomalous increase in the vicinity of the dielectric transition temperature. The Zn_1-xMg_xO thin films exhibit well-defined polarization hysteresis loop, with a remanent polarization of 0.2 µC/cm² and coercive field of 8 kV/cm at room temperature.