• Journal of Adhesion and Interface
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• v.4 no.3
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• pp.14-20
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• 2003

In order to study the radiation curing behavior of poly(ethylene glycol 400) dimethacrylate and ethylene glycol dimethacrylate, we investigated the influence of temperature and photoinitiator concentration by photo-DSC. As the number of ethylene glycol unit, the concentration of photoinitiator, and the reaction temperature increased, the reaction speed of PEG400DMA and EGDMA increased. Although the reaction speed of PEG400DMA was lower than EGDMA, the overall conversion of PEG400DMA was high.

• Journal of Hydrogen and New Energy
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• v.32 no.6
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• pp.656-662
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• 2021

For the high efficiencies of quantum dot-sensitized solar cells (QDSCs), it is important to control the severe electron recombination at the interface of photoanode/electrolyte. In this work, we optimize the surface passivation process of ZnS/SiO₂ double overlayers for the enhanced photovoltaic performances of QDSCs. The overlayers of zinc sulfide (ZnS) and SiO₂ are coated on the surface of QD-sensitized photoanode by successive ionic layer adsorption and reaction (SILAR) method, and sol-gel reaction, respectively. In particular, for the sol-gel reaction of SiO₂, the influences of temperature of precursor solution are investigated. By application of SiO₂ overlayers on the ZnS-coated photoanode, the conversion efficiency of QDSCs is increased from 5.04% to 7.35%. The impedance analysis reveals that the electron recombination at the interface of photoanode/electrolyte is obviously reduced by the SiO₂ overlayers.

• Electrical & Electronic Materials
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• v.16 no.9
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• pp.63.2-64
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• 2003

Epitaxial yttrium-stabilized HfO$_2$ thin films were deposited on p-type (100) Si substrates by pulsed laser deposition at a relatively lower substrate temperature of 550. Transmission electron microscopy observation revealed a fixed orientation relationship between the epitaxial film and Si; that is, (100)Si.(100)HfO$_2$ and [001]Si/[001]HfO$_2$. The film/Si interface is not atomically flat, suggesting possible interfacial reaction and diffusion, X-ray photoelectron spectrum analysis also revealed the interfacial reaction and diffusion evidenced by Hf silicate and Hf-Si bond formation at the interface. The epitaxial growth of the yttrium stabilized HfO$_2$ thin film on bare Si is via a direct growth mechanism without involoving the reaction between Hf atoms and SiO$_2$ layer. High-frequency capacitance-voltage measurement on an as-grown 40-A yttrium-stabilized HfO$_2$ epitaxial film yielded an dielectric constant of about 14 and equivalent oxide thickness to SiO$_2$ of 12 A. The leakage current density is 7.0${\times}$ 10e-2 A/$\textrm{cm}^2$ at 1V gate bias voltage.

• Proceedings of the Materials Research Society of Korea Conference
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• 1992.05a
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• pp.78-79
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• 1992

• Proceedings of the Materials Research Society of Korea Conference
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• 1992.05a
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• pp.82-83
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• 1992

• Proceedings of the Materials Research Society of Korea Conference
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• 1996.11a
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• pp.52-52
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• 1996

• Proceedings of the Materials Research Society of Korea Conference
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• 2001.11a
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• pp.86-86
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• 2001

• Proceedings of the Korean Vacuum Society Conference
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• 2008.08a
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• pp.258-258
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• 2008

• Proceedings of the Korean Vacuum Society Conference
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• 1992.07a
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• pp.89-90
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• 1992

• Journal of Welding and Joining
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• v.21 no.2
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• pp.35-41
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• 2003

Sintered alumina ceramics were joined by 2 kinds of SiO$_2$-CaO-A1$_2$O$_3$ glass solders having a similar expansivity as alumina. Wetting of glass/alumina was examined by sessile drop method. The observation of interface and bending strength related to alumina/glass/alumina systems were investigated by means of SEM/EDX and 4-point bending test. the result are summarized as follow: (1) Wetting of glass solders on alumina was good at temperatures higher than 145$0^{\circ}C$. (2) When the joining temperature wan high, diffusion and/or reactions between solder md alumina took place at the interface. These diffusions and reactions occurring at the interface greatly affected the bending strength of joining body. (3) Highest strength corresponding to 80% that of alumina was obtained by the solder of 35SiO$_2$-35CaO-30A1$_2$O$_3$(wt%) glass.