Highly Transparent and Surface-Plasmon-Enhanced Visible-Photodetector Based on Zinc Oxide Thin-Film Transistors with Heterojunction Structure

Abstract

Highly transparent zinc oxide (ZnO)-based thin-film transistors (TFTs) with gold nanoparticles (AuNPs) capable of detecting visible light were fabricated through spray pyrolysis on a fluorine-doped tin oxide substrate. The spray-deposited channel layer of ZnO had a thickness of approximately 15 nm, and the thickness exhibited a linear increase with an increasing number of sprays. Furthermore, the ZnO thin-film exhibited a markedly smoother channel layer with a significantly lower surface roughness of 1.84 nm when the substrate was 20 cm from the spray nozzle compared with when it was 10 cm away. Finally, a ZnO and Au-NP heterojunction nanohybrid structure using plasmonic energy detection as an electrical signal, constitutes an ideal combination for a visible-light photodetector. The ZnO-based TFTs convert localized surface plasmon energy into an electrical signal, thereby extending the wide band-gap of materials used for photodetectors to achieve visible-light wavelength detection. The photo-transistors demonstrate an elevated on-current with an increase of the AuNP density in the concentration of 1.26, 12.6, and 126 pM and reach values of 3.75, 5.18, and 9.79 × 10−7 A with applied gate and drain voltages. Moreover, the threshold voltage (Vth) also drifts to negative values as the AuNP density increases.

Photovoltatronics: intelligent PV-based devices for energy and information applications

“…On this aspect, to enable large-scale manufacturing of PV-IEAs with embedded sensors, we expect that future research will focus on seamless integration of sensors onboard of PV modules, e.g. (i) through integration within the module laminate of thin-film transistors (TFTs) to be used as thermal sensors 75,76 and thin-film photodetectors (TFPs) to be used as optical sensors; 77 or (ii) integration within the module laminate of glass fibers (or other waveguides) with distributed Bragg reflectors, e.g. Fiber Bragg Grating (FBG) arrays, to be used as temperature and strain sensors; 78,79 or (iii) sensors can be integrated directly on the solar cell, e.g.…”

Understanding the Role of Temperature and Drain Current Stress in InSnZnO TFTs with Various Active Layer Thicknesses

“…Over the past decade, the mobility (µ) of TFTs employing these semiconductors, such as InGaZnO, has greatly increased, and is comparable to that of polysilicon-based devices [7]. These metal oxide semiconductors also possess promise for various optoelectronic applications, including photodetectors and solar cells [8][9][10][11]. Inspired by the achievement of metal oxide films, another category of these materials, called InSnZnO (ITZO), was studied by our group in 2012 [12].…”