Publications by authors named "S Meskinis"

This study explores the low-temperature synthesis of graphene using plasma-enhanced chemical vapor deposition (PECVD), emphasizing the optimization of process parameters to achieve controlled growth of pristine and hydrogenated graphene. Graphene films were synthesized at temperatures ranging from 700 °C to as low as 400 °C by varying methane (25-100 sccm) and hydrogen (25-100 sccm) gas flow rates under 10-20 mBar pressures. Raman spectroscopy revealed structural transitions: pristine graphene grown at 700 °C exhibited strong 2D peaks with an I(2D)/I(G) ratio > 2, while hydrogenated graphene synthesized at 500 °C showed increased defect density with an I(D)/I(G) ratio of ~1.

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In the present research, hexagonal boron nitride (h-BN) films were deposited by reactive high-power impulse magnetron sputtering (HiPIMS) of the pure boron target. Nitrogen was used as both a sputtering gas and a reactive gas. It was shown that, using only nitrogen gas, hexagonal-boron-phase thin films were synthesized successfully.

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The high surface area and transfer-less growth of graphene on dielectric materials is still a challenge in the production of novel sensing devices. We demonstrate a novel approach to graphene synthesis on a C-plane sapphire substrate, involving the microwave plasma-enhanced chemical vapor deposition (MW-PECVD) technique. The decomposition of methane, which is used as a precursor gas, is achieved without the need for remote plasma.

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Article Synopsis
  • Researchers developed biosensors using graphene field-effect transistors (G-FETs) to detect the COVID-19 spike S protein and its receptor, ACE2.
  • They compared directly synthesized graphene on silicon substrates with commercially transferred graphene on glass, finding the former to have superior sensitivity.
  • Both G-FETs achieved a detection limit as low as 10 attograms/mL, with a notable voltage shift indicating the presence of the spike S protein at various concentrations.
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Herein we investigated hydrophilic surface modification of SiO containing amorphous hydrogenated carbon nanocomposite films (DLC:SiO) via the use of atmospheric oxygen plasma treatment. The modified films exhibited effective hydrophilic properties with complete surface wetting. More detailed water droplet contact angle (CA) measurements revealed that oxygen plasma treated DLC:SiO films maintained good wetting properties with CA of up to 28 ± 1° after 20 days of aging in ambient air at room temperature.

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