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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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Correlation between plasma characteristics, morphology, and microstructure of sputtered CuAl alloy films with varied target geometry
Abstract The effect of target geometry on coating microstructure and morphology is correlated to changes in deposition conditions, plasma characteristics, and film growth during planar and hollow cathode sputtering. The sputtering plasma properties for the two target geometries were characterized via Langmuir probe analysis as a function of power density and Ar pressure to determine the evolution of ion density for each configuration. Films were then synthesized at the low (0.4 W cm−2) and high (1.2 W cm−2) power densities and characterized using x-ray diffraction, scanning electron microscopy, and electron backscatter diffraction to link changes in texturing, morphology, and microstructure with variations in ion density and sputtering deposition conditions caused by target geometry. It was observed that varying target geometry led to an over threefold increase in deposition rate, homologous temperature, and ion density, which altered the morphology and texture of the film without significant changes to the grain size.
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- Award ID(s):
- 2106597
- PAR ID:
- 10392870
- Publisher / Repository:
- IOP Publishing
- Date Published:
- Journal Name:
- Materials Research Express
- Volume:
- 10
- Issue:
- 1
- ISSN:
- 2053-1591
- Page Range / eLocation ID:
- Article No. 016402
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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