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

Abstract

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 (Si3N4) 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 × 107 Jones), outstanding external quantum efficiency (∼1.6 × 103%), and a large on/off current ratio (∼1.5 × 102) 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.