A 3D UV Photodetector Based on TiO2 Nanoparticles Decorated Microtubular Graphene FET

This paper demonstrates a sensitive three-dimensional (3D) ultraviolet (UV) photodetector, which is fabricated by decorating a 3D tubular graphene field-effect transistor (GFET) with solution-synthesized titanium dioxide (TiO ₂ ) nanoparticles (NPs). The photoresponsivity of the device is up to 79.25 A/W, under a source-drain voltage of 0.1 V and zero gate voltage. Strong UV absorption of TiO ₂ NPs, coupled with the optical field enhancement of 3D optical resonant microcavity, should be responsible for the high photoresponsivity. Moreover, the photoresponse can be easily tuned by applying a small source-drain voltage or gate voltage. This study paves a simple and feasible way to fabricate highly sensitive, cost-efficient, and integrable 3D UV photodetectors.