Aligned CuO nanowire array for a high performance visible light photodetector

Abstract

Recently, copper oxide (CuO) has drawn much attention as a promising material in visible light photodetection with its advantages in ease of nanofabrication. CuO allows a variety of nanostructures to be explored to enhance the optoelectrical performance such as photogenerated carriers scattering and bandgap engineering. However, previous researches neglect in-depth analysis of CuO’s light interaction effects, restrictively using random orientation such as randomly arranged nanowires, single nanowires, and dispersed nanoparticles. Here, we demonstrate an ultra-high performance CuO visible light photodetector utilizing perfectly-aligned nanowire array structures. CuO nanowires with 300 nm-width critical dimension suppressed carrier transport in the dark state and enhanced the conversion of photons to carriers; additionally, the aligned arrangement of the nanowires with designed geometry improved the light absorption by means of the constructive interference effect. The proposed nanostructures provide advantages in terms of dark current, photocurrent, and response time, showing unprecedentedly high (state-of-the-art) optoelectronic performance, including high values of sensitivity (S = 172.21%), photo-responsivity (R = 16.03 A/W, λ = 535 nm), photo-detectivity (D* = 7.78 × 1011 Jones), rise/decay time (τr/τd = 0.31 s/1.21 s).

Screen-Printable Silver Paste Material for Semitransparent and Flexible Metal–Semiconductor–Metal Photodetectors with Liquid-Phase Procedure

“…Other related studies for visible light photodetectors are introduced in the following statements: J. B. Yoon et al fabricated a perfectly aligned CuO nanowire array on a silicon dioxide (SiO 2 ) nanograting substrate as a visible light photodetector, and the photosensitivity was 172.21% in the visible light range under 22.5 μW/cm 2 [ 45 ]; T. R. Yew et al synthesized Co-doped ZnFe 2 O 4 thin films on a boron-doped silicon substrate as a visible light photodetector, and the photosensitivity was 181 (1.81 × 10 4 %) with 400 °C annealing at a wavelength of 630 nm under 17.9 W/m 2 [ 46 ]. Compared to the reference works, our device reached the same order of visible light photosensitivity under 19.5 W/m 2 .…”

Sensing Capabilities of Single Nanowires Studied with Correlative In Situ Light and Electron Microscopy

“…As shown in the literature, nanowires have versatile application possibilities in electrical, , optical, , and sensor , devices. With this study, we demonstrate the sensing capability of single nanowires by using correlative microscopy techniques.…”

Recent innovations in the technology and applications of low-dimensional CuO nanostructures for sensing, energy and catalysis

“…Thermal oxidation was used recently to fabricate detectors with a high level of sensitivity, as well as a fast and stable photoresponse to visible light, using well aligned copper oxide nanowires. 96 The absorption of visible light was increased substantially by exploiting the interference effects that occur in nanowire arrays of certain geometry. The desired combination of geometry and alignment was realized through the use of an SiO 2 template that was fabricated using repeated cycles of wet-chemical oxidation and etching, as they enable the generation of 3D arrays of regularly spaced, well-aligned nanoscale structures on larger surfaces with high (1 nm) resolution (Fig.…”