Contact Printed ZnO Nanowires Based Flexible Photosensitive Devices for Large Area Smart Sensing

Zinc oxide (ZnO) nanowires (NWs) are attractive for development of sensitive optoelectronic sensors due to their wide bandgap, high aspect ratio, large surface area, and tunable properties. Due to their abundant surface states, ZnO NWs based devices also experience the bias stress instability, which could open new avenues for development of new sensors, if handled appropriately. Herein, we demonstrate how the controlled gate stress bias led bidirectional tuning of threshold voltage could be used to develop printed ZnO NW based photosensitive devices. The response of ZnO-NWs based devices to pulse stimuli shows potential for precise conductance control, resembling synaptic behavior. The active tuning of device properties demonstrated here has potential for near-sensor or in-sensor computing in large area smart sensing applications such as artificial retina.