Hysteretic metal-ferroelectric-semiconductor capacitors based on PZT/ZnO heterostructures

Interfacing of ferroelectric and semiconductor materials provides a means of coupling unique properties associated with ferroelectric materials to high performance semiconductor devices. In this work we report the electronic properties of ferroelectric/ZnO heterostructures, where (Pb, Zr) TiO3 (PZT) is used as a prototypical ferroelectric oxide. Metal-PZT-metal structures demonstrate ferroelectric hysteresis with remanent polarization of 28 mu C cm(-2) and coercive field of 75 kV cm(-1) for a loop of 15V. The metal-PZT-ZnO capacitor structures demonstrate a characteristic metal-insulator-semiconductor capacitance-voltage (C-V) behaviour with a hysteretic memory window of approximately 4V. The heterostructure C-V characteristics do not change significantly with varying frequency. Metal-PZT-ZnO capacitors are also used as part of a simple RLC circuit to demonstrate the ability to shift resonant frequency of the circuit with switching ferroelectric polarization.