Recent Progress in Ohmic/Schottky‐Contacted ZnO Nanowire Sensors

Abstract

We review the recent progress of zinc oxide (ZnO) nanowire sensors with ohmic‐contacted and Schottky‐contacted configurations and the enhancement of the performances of Schottky‐contacted ZnO NW sensors (SCZNSs) by the piezotronic effect. Comparing with the traditional ohmic‐contacted ZnO NW sensors (OCZNSs), the SCZNSs have higher sensitivities and faster responses controlled by the barrier height at the metal‐semiconductor (M‐S) interface. The piezotronic effect was applied to tune the Schottky barrier height (SBH) with the strain‐induced piezoelectric polarization charges at the interface of the M‐S contact. The piezotronic effect can thus improve the detection limitation, sensitivity, and response time of the SCZNSs in different applications, such as UV detection, gas and bio/chemical sensing. These piezotronic‐enhanced SCZNSs may find potential applications in human‐machine interfacing and flexible electronics skin technologies.