High-performance piezoelectric gate diode of a single polar-surface dominated ZnO nanobelt

We report a piezoelectric gated diode that is composed of a single ZnO nanobelt with +/-(0001) polar surfaces being connected to an indium tin oxide (ITO) electrode and an atomic force microscopy (AFM) tip, respectively. The electrical transport is controlled by both the Schottky barrier and the piezoelectric barrier modulated by the applied forces. The diode exhibits a high ON/OFF current ratio (up to 1.6 x 10(4)) and a low threshold force of about 180 nN at 4.5 V bias. The electrical hysteresis is suggested to be attributed to be carrier trapping in the piezoelectric electric field.