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In this paper, high-performance UV photodetectors have been demonstrated based on indium oxide (In2O3) thin films of approximately 1.5–2 μm thick, synthesized by a simple and quick plasma sputtering deposition approach. After the deposition, the thin-film surface was treated with 4–5 nm-sized platinum (Pt) nanoparticles. Then, titanium metal electrodes were deposited onto the sample surface to form a metal–semiconductor–metal (MSM) photodetector of 50 mm2 in size. Raman scattering spectroscopy and scanning electron microscope (SEM) were used to study the crystal structure of the synthesized In2O3 film. The nanoplasmonic enhanced In2O3-based UV photodetectors were characterized by various UV wavelengths at different radiation intensities and temperatures. A high responsivity of up to 18 A/W was obtained at 300 nm wavelength when operating at 180 °C. In addition, the fabricated prototypes show a thermally stable baseline and excellent repeatability to a wide range of UV lights with low illumination intensity when operating at such a high temperature.
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This content will become publicly available on June 25, 2026
Machine Learning-Assisted Multi-Wavelength Perception Enabled by Ultrathin, Large-Area Printed Indium Oxysulfide Phototransistors
We present a method of fabricating uniform, large area indium oxysulfide (InOxSy) films using a vacuum-free continuous liquid metal printing method (CLMP) and sulfurization process for high-performance multi-wavelength photodetection. CLMP enables rapid printing of wide area (>10 cm2/s) metal oxide films of single nm-scale thickness at process temperatures just above 150 °C, which can be partially converted to metal oxy-chalcogenide thin films at back-end-of line (BEOL) process temperatures. Phototransistors fabricated from 16 nm-thick InOxSy achieved responsivities as high as 280 A/W and respond to wavelengths as long as 630 nm, enabling both classification of multiple wavelengths and readout of intensity assisted by machine learning models.
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- PAR ID:
- 10604932
- Publisher / Repository:
- IEEE Explore
- Date Published:
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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