Self-Powered Photodetector Fabricated from a Single-Charge-Transfer Complex Nanowire Grown In Situ between Prefabricated Electrodes on an Si₃N₄ Membrane

Power consumption in an electronic circuit is one of the serious challenges that need to be improved to achieve a durable future. A photodetector is one such electronic device that consumes a huge external power to operate. This motivated the researchers to concentrate on self-powered optical photodetectors that can operate without external bias. On the contrary, building a device on a transparent film or nanomembrane has great importance in the field of electronic skins, and lightweight and intelligent wearables technology. Here, we have reported the fabrication and characterization of a self-power optical photodetector device based on a single Cu:7,7,8,8-tetracyanoquinodimethane nanowire (Cu:TCNQ NW) of length ∼500 nm and diameter ∼50 nm. The NW photodetector device was fabricated on a silicon nitride (Si 3 N 4 ) membrane window (size = 100 μm × 100 μm, membrane thickness ∼100 nm) to meet the demands of a lightweight and transparent technology. The reported self-powered single-NW photodetector exhibits excellent photoresponsivity (∼5.5 A/W), high detectivity (∼ 7 × 10 7 Jones), outstanding external quantum efficiency (∼1.6 × 10 3 %), and a large on/off current ratio (∼1.5 × 10 2 ) at 49 nW optical power. The analysis reveals that the contribution is due to photocarrier generation, radial built-in-field on the NW’s surface, and barrier height reduction during illumination. Self-powered optical photodetectors, in particular, have enormous potential as novel emerging self-driven optoelectronic devices.