• Proceedings of the Korean Vacuum Society Conference
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• 2015.08a
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• pp.86.2-86.2
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• 2015

Cu2ZnSn(S,Se)4 thin film solar cells have been fabricated using sputtered Cu/Sn/Zn metallic precursors on Mo coated sodalime glass substrate without using a toxic H2Se and H2S atmosphere. Cu/Sn/Zn metallic precursors with various thicknesses were prepared using DC magnetron sputtering process at room temperature. As-deposited metallic precursors were sulfo-selenized inside a graphite box containing S and Se pellets using rapid thermal processing furnace at various sulfur to selenium (S/Se) compositional ratio. Thin film solar cells were fabricated after sulfo-selenization process using a 65 nm CdS buffer, a 40 nm intrinsic ZnO, a 400 nm Al doped ZnO, and Al/Ni top metal contact. Effects of sulfur to selenium (S/Se) compositional ratio on the microstructure, crystallinity, electrical properties, and cell efficiencies have been studied using X-ray diffraction, Raman spectroscopy, field emission scanning electron microscope, I-V measurement system, solar simulator, quantum efficiency measurement system, and time resolved photoluminescence spectrometer. Our fabricated Cu2ZnSn(S,Se)4 thin film solar cell shows the best conversion efficiency of 9.24 % (Voc : 454.6 mV, Jsc : 32.14 mA/cm2, FF : 63.29 %, and active area : 0.433 cm2), which is the highest efficiency among Cu2ZnSn(S,Se)4 thin film solar cells prepared using sputter deposited metallic precursors and without using a toxic H2Se gas. Details about other experimental results will be discussed during the presentation.

• 한국생물공학회:학술대회논문집
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• 2003.04a
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• pp.393-397
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• 2003

P. aeruginosa F722 produces biosurfactant (BS) while degrading hydrocarbons. BS production was 0.78 $g/{\ell}$ on the C-medium. However, BS production increased by 1.66 $g/{\ell}$ on the condition of 0.05% (w/v) $NH_4Cl+0.1%$ (w/v) yeast extract and 3.0% (w/v) glucose, which was proved to be advantageous to BS production. In the condition of aeration of 1.0 liter per minute (LPM), BS production was increased 20% (1.94 $g/{\ell}$)more than 1.66 $g/{\ell}$ produced when the air was not supplied. Moreover, the velocity of glucose degradation at both of log and stationary growth phases increased from 0.25 and 0.18 $h^{-1}$ to 0.33 and 0.29 $h^{-1}$ respectively when the air was supplied. Besides, BS activity was more stabilized on the condition of air supply.