• The Korean Journal of Ecology
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• v.15 no.4
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• pp.355-363
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• 1992

Nitrate reductase activity(NRA) and induced NRA were compared in 4 species of moss ctenidium molluscum, homalothecium, tortella tortusa and neckera crispa collected from limestone in england. the NRA and dry weight of the c. molluscum were also measured after spraying with acidic deposition adjusted to ph 5.6, 4.6, 3.6 and 2.8 with one of two molar ratios of nitric to sulfuric acid, i.e. 1:0(N alone) and 1:2(1N+2S) for 20 days. All 4 species showed high NR leavels in the upper part of cut shoots and occurred maximum inducation of NRA within 6h. c. molluscum had the highest NRA levels among 4 species. after daily spraying of acidic deposition, NRA of c. molluscum was increased much more largely at ph 6 and ph 3.6 derived from N alone than from 1N+2S. However that was decreased at ph 2.8 derived both from N alone and 1N+2S . Decline of dry weight had occurred at ph 3.6 and 2.8 derived both from N alone and 1N+2S. Whereas substantial fertilization effect was observed at ph 4.6 derived from N alone. the data suggest that c. molluscum are able to utilize nitrate more effectivery than any other species, and NRA induction are more sensitive than growth response to nitrogen content of acidicdeposition in a short- term. however toxic effects was detected at high $NO_3$ supply and low phacidic deposition.

• Journal of the Korean institute of surface engineering
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• v.39 no.2
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• pp.70-75
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• 2006

As technology advances, there is a demand for development of hard, solid lubricant coating. (Ti,Cr)N-$MoS_2$, films were deposited on SKD 11 tool steel substrate by co-deposition of $MoS_2$, with (Ti,Cr)N using a D.C. magnetron sputtering process. The influence of the $N_2/Ar$ gas ratio, the deposition temperature, the amount of $MoS_2$ in the films, and the bias voltage on the mechanical and the structural properties of the films were investigated. Wear tests were performed on the films deposited in various conditions.

• Journal of the Korean Society for Heat Treatment
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• v.3 no.1
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• pp.1-7
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• 1990

To investigate the influence of r.f. power and electrode distance on the TiN deposition, TiN films were deposited onto STC3, STD11 steel and Si-wafer from gas mixtures of $TiC_4/N_2/H_2$ using the radio frequency plasma assisted chemical vapor deposition. The crystallinity of TiN film could be improved by the increase of r.f. power and the decrease of electrode distance. The TiN coated layer contains chlorine, its content were decreased with increasing r.f. power as well as decreasing electrode distance. And the thickness of deposited TiN was largely affected by r.f. power and electrode distance. The hardness of deposited TiN reached a maximum value of about Hv 2,000.

• Journal of the Korean Society for Heat Treatment
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• v.2 no.4
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• pp.1-10
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• 1989

To investigate the influence of temperature on the TiN film, it was deposited on the STC-3 steel and Si-wafer from $TiCl_4/N_2/H_2$ gas mixture by using the radio frequency plasma assisted chemical vapor deposition. The deposition was performed at temperature of $400^{\circ}C-500^{\circ}C$. The results showed that crystalline TiN film was deposited over $480^{\circ}C$, and all specimens showed the crystalline TiN X-ray diffraction peaks after vacuum heat treatment for 3 hrs, at $1000^{\circ}C$, $10^{-5}torr$. While the film thickness was increased above $480^{\circ}C$, it was decreased under $480^{\circ}C$ as temperature increased. And the contents of titanium were increased and it of chlorine were decreased as temperature increased. Because temperature increase was attributed to the increase in the density of TiN film, surface hardness of TiN film was increased with temperature.

• Proceedings of the Korean Society Of Semiconductor Equipment Technology
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• 2006.05a
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• pp.135-138
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• 2006

OLEDs are attractive because of possible application in display with low operating voltage, low power consumption, self-emission and capability of multicolor emission by the selection of emissive material. We investigated the effects of deposition rate on the electrical characteristics, physical characteristics and optical characteristics of OLEDs in the ITO(indium-tin-oxide)/N,N'-diphenyl-N,N'-bis(3-methyphenyl)-1,1'-biphenyl-4,4'-diamine(TPD)/tris(8-hydroxyquinoline)aluminum($Alq_3$)/Al device. We measured current density, luminous flux and luminance characteristics of devices with varying deposition rates of TPD and $Alq_3$. It has been found that optimal deposition rate of TPD and $Alq_3$ were respectively $1.5{\AA}/s$ from the device structure. An AFM measurement results, surface roughness of the deposited film was the lowest when deposition rate was $1.5{\AA}/s$.

• Proceedings of the KIEE Conference
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• 1994.07b
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• pp.1243-1245
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• 1994

SiN films were deposited in $Si_2H_6$(99.9%), $NH_3$(99.99%) gas mixture with carrier gas $N_2$ on Si substrate by ArF Excimer Laser CVD. SiN film deposition conditions that are substrate temperature and Laser average power were varied in order to investigate the dependence of SiN film on the condition. A post-deposition anneal was performed to examine variation of fixed charge density in the films. The deposition rate was increased as the substrate temperature and Laser power were increased during film deposition. The refractive index was increased with increasing substrate temperature, but it didn't have the dependence on Laser power. The fixed charge density was decreased when a post-deposition anneal was performed.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.22 no.1
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• pp.74-80
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• 2009

In the structure of ITO/N,N'-diphenyl-N,N' bis (3-methylphenyl)-1,1'-biphenyl-4,4'-diamine(TPD)/tris (8-hydroxyquinoline)aluminum($Alq_3$)/Al device, we studied the efficiency improvement of organic light-emitting diodes due to variation of deposition rate of hole transport layer (TPD) materials using hole-size of crucible boat. The thickness of TPD and $Alq_3$ was manufactured 40 nm, 60 nm, respectively under a base pressure of $5{\times}10^{-6}$ Torr using a thermal evaporation. The $Alq_3$ used for an electron-transport and emissive layer were evaporated to be at a deposition rate of $2.5\;{\AA}/s$. When the deposition rate of TPD increased from 1.5 to $3.0\;{\AA}/s$, we studied the efficiency improvement of TPD using the hole-size of crucible is 1.0 mm. When the deposition rate of TPD is $2.5\;{\AA}/s$, we found that the average roughness is rather smoother, the luminous efficiency the external quantum efficiency is superior to the others. Compared to the two from the devices made with the deposition rate of TPD is $2.0\;{\AA}/s$ and $3.0\;{\AA}/s$, the external quantum efficiency was improved by four-times and two-times, respectively.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2006.04a
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• pp.54-55
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• 2006

Organic light-emitting diodes(OLEOs) are attractive because of possible application in display with low operating voltage, low power consumption, self-emission and capability of multicolor emission by the selection of emissive material. We investigated the effects of deposition rate on the electrical characteristics, physical characteristics and optical characteristics of OLEOs in the ITO(indium-tin-oxide)/N.N'-diphenyl-N,N'-bis(3-methyphenyl)-1,1'-biphenyl-4,4'-diamine(TPD)/tris(8-hydroxyquinoline)aluminum($Alq_3$)/Al device. We measured current density, luminous flux and luminance characteristics of devices with varying deposition rates of TPD and $Alq_3$. It has been found that optimal deposition rate of TPD and $Alq_3$ were respectively $1.5{\AA}/s$ from the device structure. An AFM measurement results, surface roughness of the deposited film was the lowest when deposition rate was $1.5{\AA}/s$.

• Journal of the Korean Society for Heat Treatment
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• v.5 no.1
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• pp.1-12
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• 1992

In order to improve adhesive force of TiN film, we sputtered titanium as interlayer before TiN deposition by Plasma Enhanced Chemical Vapour Deposition. We observed changes of hardness and adhesion at a various thickness of titanium interlayer and also examined analysis. At the critical thickness of the titanium interlayer(about $0.2{\mu}$), adhesive force of TiN films were promoted mostly. But over the critical thickness, a marked reduction of adhesive force was showed, because of the internal stress of titanium interlayer. From AES analysis, the adhesion improvement of TiN films was mainly caused by nitrogen diffusion into titanium interlayer during TiN deposition process which relieved stress concentration at TiN coating-substrate interface.

• Environmental Sciences Bulletin of The Korean Environmental Sciences Society
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• v.10 no.S_2
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• pp.55-63
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• 2001

This work employs two models to quantify the size-segregated dry deposition fluxes of particle-bound N $O_3$$^{[-10]}$ , N $H_4$$^{+}$, and S $O_4$$^{2-}$ along the coastal area of Jeju Island based on the chemical composition data of aerosol collected during the springtime of 1995. The two approaches produced fairly comparable results, despite the feature differences between the two models. The modelling results obtained indicated that the mean dry deposition velocity was around 0.4 cm $s^{-1}$ for N $O_3$$^{[-10]}$ , 0.2 cm $s^{-1}$ for N $H_4$$^{+}$, and 0.3 cm $s^{-1}$ for S $O_4$$^{2-}$, and the dry deposition flux varied between 371~1368 $\mu\textrm{g}$ $m^{-2}$ da $y^{-1}$ for nitrate, 28~625 $\mu\textrm{g}$ $m^{-2}$ da $y^{-1}$ for ammonium, and 957~6088 $\mu\textrm{g}$ $m^{-2}$ da $y^{-1}$ for sulfate. Although difficulties in collecting giant and/or fine particles limited the understanding of the mass size distribution of particles and thus the ability to refine estimates of the dry deposition flux for the particulate matter, both models were still able to offer sufficient realism to explain the features of the available data collected from the coastal area of Jeju Island.and.