• Journal of Radiation Protection and Research
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• v.29 no.3
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• pp.165-172
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• 2004

Rice plants were exposed to $I_2$ vapor for 80 min at different growth stages in an exposure box to investigate the parameters concerning direct plant contamination. Deposition velocity $(m\;s^{-1})$ of the $I_2$ vapor for the straws was in the range of $1.4{\times}10^{-5}-1.3{\times}10^{-4}$ depending on the exposure time, being comparatively low during the earlier part of the plant growth. Ear deposition velocity was in the range of $2.5{\times}10^{-5}-6.7{\times}10^{-5}$. Whole-plant deposition velocity was in the range of $1.4{\times}10^{-5}-1.8{\times}10^{-4}$ with the highest from the exposure performed on Aug. 18 (7 d after the start of heading). The time-dependent variation generally decreased when the deposition velocity was normalized to the biomass density No noteworthy tendency in the deposition velocity was observed with regard to the temperature, sunlight and humidity. Translocation factor for the hulled seeds was $3.3{\times}10^{-5}-4.7{\times}10^{-4}$ with the highest from the Aug. 23 exposure. It was found that a leaf deposition even before the ear emergence resulted in a considerable seed translocation.

• Proceedings of the Korean Institute of Surface Engineering Conference
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• 2016.11a
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• pp.194.1-194.1
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• 2016

The present study investigated the effect of zincate treatment time on the dissolution behavior and the deposition of copper by immersion process and electroplating process on AZ31 Mg alloy substrate in a copper pyrophosphate bath. Without zincate pretreatment, the AZ31 Mg substrate quickly dissolved in the copper pyrophosphate solution although an external cathodic current was applied. The copper layers deposited on non-zincate treated AZ31 Mg alloy substrate by both immersion and electroplating processes showed very porous structure and very poor adhesion. With increasing zincate treatment time up to 2 min, the dissolution of AZ31 substrate in pyrophosphate solution rapidly decreased and the deposited copper layer was less porous and exhibited stronger adhesion. The immersion of AZ31 Mg sample in zincate solution for 5 min was found as a critical time for producing a non-porous and adherent electrodeposited copper layer on AZ31 Mg alloy. The optimum zincating time can be determined by observing the open circuit potential (OCP) of AZ31 Mg alloy samples in a copper pyrophosphate electroplating bath. The OCP reached a stable value of about -0.10 V (vs. SCE) after 5 min of immersion in the copper pyrophosphate electroplating solution.

• Journal of the Korean Vacuum Society
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• v.7 no.s1
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• pp.100-105
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• 1998

This paper describes the preparation of Pt-and $TiO_2$-doped $Nb_2O_5$ thin film by Ion-Beam-Enhanced Deposition. Platinum and titanium doping, and Nb2O5 deposition were carried out in situ. The dependence of oxygen sensing properties on the amounts of Pt and Ti dopant in the $Nb_2O_5$ film was investigated. There were the highist sensitivity, the lowest temperature coefficient and the shortest responce time at doping of 5 mol% $TiO_2$ and 0.3 mol%Pt

• Proceedings of the Materials Research Society of Korea Conference
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• 2011.10a
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• pp.28.1-28.1
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• 2011

We deposited the carbon films on Ni substrates by thermal atomic layer deposition (th-ALD), for the first time, using carbon tetrabromide ($CBr_4$) precursors and H2 reactants at two different temperatures (573 K and 673 K). Morphology of carbon films was characterized by scanning electron microscopy (SEM). The carbon films having amorphous carbon structures were analyzed by X-ray photoemission spectroscopy (XPS) and Raman spectroscopy. As the working temperature was increased from 573 K to 673 K, the intensity of C1s spectra was increased while that of O1s core spectra was reduced. That is, the purity of carbon films containing bromine (Br) atoms was increased. Also, the thin amorphous carbon films (ALD 3 cycle) were transformed to multilayer graphene segregated on Ni layer, through the post-annealing and cooling process.

• Proceedings of the Korean Vacuum Society Conference
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• 2013.02a
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• pp.282-282
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• 2013

The antimony sulfide ($Sb_2S_3$) thin films were deposited using the gas phase method which known as atomic layer deposition (ALD) on mesoporous micro-films. Tris (dimethylamido) antimony (III[$(Me_2N)_3Sb$] and hydrogensulfide ($H_2S$) were used as precursors to deposit $Sb_2S_3$. Self-terminating nature of $(Me_2N)_3Sb$ and $H_2S$ reaction were demonstrated by growth rate saturation versus precursors dosing time. Absorption spectra and extinction coefficient were investigated by UV-VIS spectroscopy. Scanning electron microscopic analysis and X-ray photoelectron spectroscopy (XPS) depth profile were employed to determine the conformal deposition.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.17 no.3
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• pp.329-332
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• 2004

ZnO thin films were grown with different plume-substrate angles by pulsed laser deposition (PLD) to control the amount of ablated species arriving on a substrate per laser shot. The angles between plume propagation direction and substrate plane (P-S angle) were 0$^{\circ}$, 45$^{\circ}$ and 90$^{\circ}$. The growth time was changed in order to adjust film thickness. From the XRD pattern exhibiting a dominant (002) and a minor (101) XRD peak of ZnO, all films were found to be well oriented along c-axis. From the AFM image, it was found that the grain size of ZnO thin film was increased, as P-S angle decreased. UV intensity investigated by PL (Photoluminescence) increased as P-S angle decreased.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2006.11a
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• pp.75-76
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• 2006

olycrystailine CdSe thin films were grown on ceramic substrate using a chemical bath deposition (CBD)method. They were annealed at various temperature and X-ray diffraction patterns were measured by X-ray diffractometer in order to study CdSe polycrystal structure. Its grain size was about 0.3 ${\mu}m$. Hall effect on this sample was measured by Van der Pauw method and studied on carrier density and movility depending on temperature. We measured also spectral response, sensitivity($\gamma$), maximum allowable power dissipation and response time on these samples.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2002.07a
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• pp.391-394
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• 2002

Transparent conductive oxides (TCO) are necessary as front electrode for most thin film solar cell. In our paper, transparent conducting aluminum-doped Zinc oxide films (ZnO:Al) were prepared by rf magnetron sputtering on glass (Corning 1737) substrate as a variation of the deposition condition. After deposition, the smooth ZnO:Al films were etched in diluted HCl (0.5%) to examine the electrical and surface morphology Properties as a variation of the time. The most important deposition condition of surface-textured ZnO films by chemical etching is the processing pressure and the substrate temperature. In low pressures (0.9 mTorr) and high substrate temperatures ($\leq$30$0^{\circ}C$), the surface morphology of films exhibits a more dense and compact film structure with effective light-trapping to apply the silicon thin film solar cells.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.58 no.8
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• pp.1566-1571
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• 2009

The discharge electrodes in ac PDP are coated with dielectric layer, and transparent MgO thin films are deposited on the dielectric layer. The main role of the MgO thin films in ac PDP is to protect the dielectric layer from sputtering by ion bombardment in the glow-discharge plasma. An additional important role of the MgO thin film is the high secondary electron emission coefficient which leads the low firing voltage and low cost of the PDP. In this paper, we investigated the relations of the crystal orientation about deposition thickness, deposition rate, temperature of substrate, and distance between the MgO tablet and the substrate. Additionally, we investigated the discharge characteristics of the AC PDP using nano-powder MgO tablet

• Proceedings of the Korean Society of Precision Engineering Conference
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• 1997.10a
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• pp.1042-1046
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• 1997

Fused deposition modelling(FDM) is a rapid prototyping(RP) process that fabricates part layer by layer by deposition of molten thennoplastic material extrude from a nozzle. RP system has many benefit. One of the benefit would be the ability to experiment with physical objects of any complexity in a relatively short period of time. But it has a matter of surface roughness and geometric accuracy. We research into a change of Surface roughness making the sphere by adjustment of extrusion in FDM.