Metal–Semiconductor–Metal UV Detectors Using Transferrable Amorphous and Crystalline Zinc-Tin-Oxide Microsphere Monolayers

Abstract

Metal−semiconductor−metal UV photodetectors consisting of transferable zinc-tin-oxide (ZTO) microsphere (MS) monolayers with different phases and sizes are reported. From the experimental results, the crystallized Zn 2 SnO 4 (c-ZTO)-MS-monolayer-based photodetectors present higher performance than amorphous ZnSnO 3 (a-ZTO)-based photodetectors. The external quantum efficiencies of the a-ZTO-and c-ZTO-MS-based UV photodetectors are 16.7% (at 320 nm) and 580.9% (at 310 nm), respectively. Moreover, the UV-to-visible rejection ratios of the a-ZTO and c-ZTO are 20 (320 nm/400 nm) and 1484 (310 nm/400 nm), respectively, indicating that both fabricated ZTO MS UV photodetectors present great visible-blind properties. To further improve the optoelectronic device performance, the c-ZTO-MSbased UV photodetector is optimized using various sphere diameters, namely, 0.79, 0.99, 1.24, and 1.51 μm. The best photodetecting properties are obtained for the 1.24 μm c-ZTO MS detector, showing a 51.1-fold improvement in photocurrent compared with the lowest level c-ZTO-based detector. These results are attributed to the different oxygen-related defect ratios in the ZTO MSs. The reported transferable ZTO-MS-monolayer-based optoelectronic devices have the potential for novel optoelectronic applications.

Inverted Configuration of Cu(In,Ga)S2/In2S3 on 3D-ZnO/ZnSnO3 Bilayer System for Highly Efficient Photoelectrochemical Water Splitting

“…Recently, zinc stannate, ZnSnO 3 (ZTO), as a ternary counterpart of ZnO and SnO 2 has been under consideration owing to its outstanding optoelectronic properties and chemical stability under harsh conditions compared to both ZnO and SnO 2 . , To date, its ecofriendly nature and high biocompatibility have increased the attraction of this material for gas sensing applications. − Unfortunately, there is not a significant study based on the implementation of this material in the PEC water splitting and energy conversion field. However, the most featured point of ZTO is the suitable band potentials with ZnO in which the valence band (VB) of ZnO lies between the VB and conduction band (CB) of ZTO.…”

Zinc–Tin Oxide Film as an Earth-Abundant Material and Its Versatile Applications to Electronic and Energy Materials

“…Oxide semiconductors can be produced with various structures, such as thin films, nanoparticles [ 84 , 85 , 86 ], microspheres [ 87 ], nanomesh [ 88 ], and nanowires [ 84 , 89 ], and have appropriate photoreactivity. Therefore, they are applied in various fields, such as gas sensors [ 90 ] and light sensors [ 91 , 92 , 93 , 94 ].…”

“…In 2020, Jung et al developed a highly efficient UV photodetector using ZTO microspheres (MS). The photodetection performance was compared according to the crystallinity of ZTO, and the performance was optimized according to the diameter of the ZTO-MS [ 87 ]. The external quantum efficiency for UV improved as the crystallinity of ZTO was increased.…”

“…( b ) I-V characteristics of photocurrent difference of c-ZTO-MS monolayers with varied MS diameters at a UV wavelength of 254 nm. The MS has diameters of 1.51 μm, 1.24 μm, 0.99 μm, and 0.79 μm, respectively (adapted from [ 87 ] with permission from American Chemical Society). ( c ) Transfer characteristics of the fabricated ZTO TFTs in different oxygen partial pressures (10 torr, 100 torr, and 760 torr) and after illumination of visible light, respectively.…”

High-Performance and Self-Powered Alternating Current Ultraviolet Photodetector for Digital Communication

“…The effective utilization of light to generate detectable electric output is the heart of modern technological applications, including space exploration, medical field, flame detection, environmental monitoring, and more importantly advanced optical communication. − Fundamentally, photoactive layer(s) is sandwiched between working electrodes, where photo-absorption-induced electron–hole (e–h) pairs are separated by an internal (built-in) potential or an external electric field, resulting in the photocurrent appeared. − Various wide bandgap materials such as zinc oxide (ZnO), tin oxide (SnO 2 ), titanium dioxide (TiO 2 ), and nickel oxide (NiO) are considered as promising materials to design ultraviolet (UV) photodetectors. However, in spite of the achievements made in the development of UV photodetectors, achieving robust performance in metal-oxide-based self-biased UV photodetectors in terms of high photoresponse and large photocurrent switching ratio is critical, which urgently demands an alternative approach to develop an efficient UV photodetector with high large-area reproducibility.…”