TUNABLE PROPERTIES OF LSCO BUFFERED PMN-PT THIN FILM CAPACITOR

Abstract

The tunable properties of Pt/PMN-PT/LSCO/Ir capacitor have been studied under different applied voltages and frequencies. The PMN-PT thin film exhibited good dielectric tunability. A tunability of 70.3% at 12 V and 100 kHz is obtained for the film under negative voltage bias. For the positive voltage bias, the tunability is 68.7% which is smaller than the value under negative voltage bias. The asymmetric distribution of charged defects is suggested as possible causes of the asymmetric capacitance–voltage (C–V) behaviors of ferroelectric capacitors. On the other hand, the frequency dependency of the capacitance's tunability indicated that the interface has strong influence on the frequency stable of tunability.