• Journal of the Microelectronics and Packaging Society
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• v.24 no.4
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• pp.79-84
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• 2017

The solar cells should be protected from the moisture and oxygen in order to sustain the properties and reliability of the devices. In this research, we prepared the protection films on the flexible plastic substrates by spray coating method using organic-inorganic hybrid solutions. The protection characteristics were studied depending on the various process conditions (nozzle distance, thicknesses of the coatings, film structures). The organic-inorganic solutions for the protection film layer were synthesized by addition of $Al_2O_3$ ($P.S+Al_2O_3$) and $SiO_2$ ($P.S+SiO_2$) nano-powders into PVA (polyvinyl alcohol) and SA (sodium alginate) (P.S) organic solution. The optical transmittances of the protection film with the thicknesses of $5{\mu}m$ showed 91%. The optical transmittance decreased from 81.6% to 73.6% with the film thickness increased from $78{\mu}m$ to $178{\mu}m$. In addition, the protective films were prepared on the PEN (polyethylene naphthalate), PC (polycarbonate) single plastic substrates as well as the Acrylate film coated on PC substrate (Acrylate film/PC double layer), and $Al_2O_3$ film coated on PEN substrate ($Al_2O_3$ film/PEN double layer) using the $P.S+Al_2O_3$ organic-inorganic hybrid solutions. The optimum protection film structure was studied by means of the measurements of water vapor transmittance rate (WVTR) and surface morphology. The protective film on PEN/$Al_2O_3$ double layer substrate showed the best water protective property, indicating the WVTR value of $0.004gm/m^2-day$.

• The Korean Journal of Mycology
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• v.23 no.2 s.73
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• pp.121-128
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• 1995

The characteristics of protein-bound polysaccharides (PBP) which were isolated and purified from the sawdust mycelia of Agrocybe cylindracea were investigated. The yield of crude protein-bound polysaccharides (Fr.CB) extracted with boiling water and precipitated with 95% ethanol, was 0.74% based on the original sawdust mycelia. The Fr.CB was purified by the membrane filtration, ion exchange chromatography and gel filtration. The Fr.B fraction of which the molecular weight is over 300 KDa, was isolated from the Fr.CB using membrane filtration, and the yield was 38.6% based on the Fr.CB. This result indicates that high molecular protein-bound polysaccharides are the dominent components of the Fr.CB. Two fractions (Fr.B-1, Fr.B-2) were also isolated from the Fr.B using ion exchange chromatography, and the yields were 17.3% (Fr.B-1) and 10.3% (Fr. B-2), respectively. The Fr.B-1 was concentrated and gel-filtrated, and the single peak, thought to be nearly pure protein-bound polysaccharides, was obtained. The yield of final fraction $(Fr.B-1-{\beta})$ was 42.5% based on the Fr.B-1. The molecular weight of $Fr.B-1-{\beta}$ was nearly 710 KDa. The monosaccharides' composition of $Fr.B-1-{\beta}$ was analized by HPLC, and glucose was the dominent component, and fucose and galactose were also detected. The result of amino acid analysis was that glutamic acid and analysis were detected to a significant level, and cysteine was not detected.

• Journal of the Korean Vacuum Society
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• v.15 no.4
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• pp.395-403
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• 2006

It is known that $MgAl_2O_4$ has higher resistance to moisture than MgO, in humid ambient MgO is chemically unstable. It reacts very easily with moisture in the air. In this study, the characteristic of $MgAl_2O_4$ and $MgAl_2O_4/MgO$ layers as dielectric protection layers for AC- PDP (Plasma Display Panel) have been investigated and analysed in comparison for conventional MgO layers. MgO and $MgAl_2O_4$ films both with a thickness of $1000\AA$ and $MgAl_2O_4/MgO$ film with a thickness of $200/800\AA$ were grown on the Cu substrates using the electron beam evaporation. $1000\AA$ thick aluminium layers were deposited on the protective layers in order to avoid the charging effect of $Ga^+$ ion beam while the focused ion beam(FIB) is being used. We obtained sputtering yieds for the MgO, $MgAl_2O_4$ and $MgAl_2O_4/MgO$ films using the FIB system. $MgAl_2O_4/MgO$ protective layers have been found th show $24{\sim}30%$ lower sputtering yield values from 0.244 up to 0.357 than MgO layers with the values from 0.364 up to 0.449 for irradiated $Ga^+$ ion beam with energies ranged from 10 kV to 14 kV. And $MgAl_2O_4$ layers have been found to show lowest sputtering yield values from 0.88 up to 0.109. Secondary electron emission coefficient(g) using the ${\gamma}$- FIB. $MgAl_2O_4/MgO$ and MgO have been found to have similar g values from 0.09 up to 0.12 for indicated $Ne^+$ ion with energies ranged from 50 V to 200 V. Observed images for the surfaces of MgO and $MgAl_2O_4/MgO$ protective layers, after discharge degradation process for 72 hours by SEM and AFM. It is found that $MgAl_2O_4/MgO$ protective layer has superior hardness and degradation resistance properties to MgO protective layer.