Investigation on Response Characteristics of Flexible Photosensors Fabricated with High-Crystalline InN Nanowires

Herein, we report the dynamic characteristics of flexible photosensors fabricated with InN nanowires and graphene. To investigate the effect of the number of graphene layers on the response characteristics, the top graphene layer was set as a single layer, and the bottom graphene layers were varied from single to quadruple layers to fabricate flexible photosensors. The response and recovery times of the as-fabricated flexible photosensor, with the triple-layer bottom graphene, were measured to be 20.6 and 24.2 ms, respectively, at an optical pulse illumination frequency of 5 Hz. The cross-point percentage was calculated to be 48.9 %, indicating a low probability of distortion in the pulse signal. The response and recovery times calculated from an equivalent circuit model composed of capacitances and resistances are in good agreement with the measured values. The flexible photosensors with fast-response characteristics demonstrated in this study could contribute to the implementation of the light-fidelity systems.