• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2001년도 추계학술대회 논문집
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• pp.126-129
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• 2001

A p-n junction was obtained by the deposition of an n-type ZnO thin film on a p-type Zn-doped InP substrate. The Zn-doped InP substrate has been made by the diffusion of Zn with sealed ampoule technique. The ZnO deposition process ws performed by pulsed laser deposition (PLD). The p-n junction was formed and showed a typical I-V characteristic. We will also discuss about the realization of an ultraviolet light-emitting diode (LED). The structure of n-ZnO/p-Zn-doped InP could be a good candidate for the realization of an ultraviolet light-emitting diode or an ultraviolet laser diode.

• The Korean Journal of Ecology
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• 제15권4호
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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.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2006년도 학술대회 및 기술세미나 논문집 디스플레이 광소자
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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 $1.5{\AA}/s$.

• 한국표면공학회:학술대회논문집
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• 한국표면공학회 2001년도 춘계학술발표회 초록집
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• pp.6-7
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• 2001

• Journal of Ecology and Environment
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• 제29권3호
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• pp.305-321
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• 2006

대기 산성 강하물 : 삼림의 질소 포화 한국의 연평균 습성 질소 강하량은 12.78(범위: $7.28{\sim}21.05)\;kgN{\cdot}ha^{-1}{\cdot}yr^{-1}$이고, 이것에 건성 질소 강하량(43%)을 합하여 추정한 총질소 강하량은 18.26(10.41-30.10) $kgN{\cdot}ha^{-1}{\cdot}yr^{-1}$이 된다. 이 질소 강하량은 유럽과 북미 북동부의 질소 강하량과 비슷한 수준이다. 대기 질소 강하량이 많은 온대 삼림은 질소로 포화된다. 질소로 포화된 삼림은 계류수와 토양에 질산이온 ($NO_3^-$)과 질산태질소/암모늄태질소이($NO_{3}^{-}-N/NH_{4}^{+}-N$)의 비가 높아지고, 잎의 질소 농도가 높아지므로 N/P비, N/K비 및 N/Mg 비가 높아지는 것으로 보아 무기 영양소 교란이 일어나며, 상해와 병해에 걸리기 쉬워지고 세근과 근균의 활성이 낮아짐으로써 생산성이 낮아진다. 그러고 혐질소성 종이 호질소성 종에 의하여 대치된다. 질소로 포화된 토양에서는 온실가스인 메탄($CH_4$)의 흡수가 감소되고 일산화질소 (NO)와 아산화질소 ($N_{2}O$)의 배출이 증가되어 지구온난화를 촉진할 수 있다. 이 종설은 한국의 33장소에서 6년 동안 ($1999{\sim}2004$) 측정한 부피가중 연평균 습성 질소 강하량이 삼림의 질소 포화 수준에 달하고, 광릉시험림분수계와 그 밖의 삼림 계류수의 $NO_3$ 유출량으로 미루어 보아 한국의 삼림에 질소 포화의 징후가 나타났음을 제시하며, 문헌 자료를 통해서 외국의 삼림에서 일어나는 질소 포화의 징후를 체계적으로 논하는 데 목적이 있다.

• 한국세라믹학회지
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• 제39권6호
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• pp.594-597
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• 2002

플라즈마 화학기상증착(PECVD)법을 이용하여 p-type Si(100) 웨이퍼에 Silicon Oxynitride(SiON) 후막을 SiH$_4$ , $N_2$O, $N_2$ 가스를 혼합하여 증착하였다. Prism coupler측정을 통해 SiON 후막의 굴절률 1.4620~1.5312을 얻었으며, rf power가 180 W에서 5.92$\mu$m/h의 증착률을 나타내었다. 증착변수에 따른 화학적 조성의 영향은 X-ray Photoelectron Spectroscopy(XPS) 을 통하여 관찰하였다. 또한, SiON 후막 증착후에 $1.5\mu$m 부근의 흡수띠를 제거하기 위해 105$0^{\circ}C$의 $N_2$ 분위기에서 2시간 동안 열처리를 행하였다.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1994년도 하계학술대회 논문집 C
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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.

• 한국기계가공학회지
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• 제7권1호
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• pp.67-74
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• 2008

In this paper, the surface characteristics of the AIP-TiN coated of the SKH51 and SKD11 steels under various deposition times are presented with emphasis on the comparison of the two materials. The micro-particle, the surface roughness, the micro-hardness, the coated layer thickness, the atomic distribution of Ti, N and Fe elements and the adhesion are measured for various deposition times. It has been shown that the micro-particle, the surface roughness, the coated layer thickness and the atomic distribution of Ti, N and Fe elements are similar for the two cases regardless of the test deposition time from 10 to 180 minutes. However, it has been shown that the micro-hardness and the adhesion of the SKH51 steel are higher than the SKD11 steel, indicating that they are much affected by the hardness of the material to be coated.

• 한국진공학회:학술대회논문집
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• 한국진공학회 2011년도 제40회 동계학술대회 초록집
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• pp.204-205
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• 2011

In thin film silicon solar cells, p-i-n structure is adopted instead of p/n junction structure as in wafer-based Si solar cells. PECVD is a most widely used thin film deposition process for a-Si:H or ${\mu}c$-Si:H solar cells. For best performance of thin film silicon solar cell, the dopant profiles at p/i and i/n interfaces need to be as sharp as possible. The sharpness of dopant profiles can easily achieved when using multi-chamber PECVD equipment, in which each layer is deposited in separate chamber. However, in a single-chamber PECVD system, doped and intrinsic layers are deposited in one plasma chamber, which inevitably impedes sharp dopant profiles at the interfaces due to the contamination from previous deposition process. The cross-contamination between layers is a serious drawback of a single-chamber PECVD system in spite of the advantage of lower initial investment cost for the equipment. In order to resolve the cross-contamination problem in single-chamber PECVD systems, flushing method of the chamber with NH3 gas or water vapor after doped layer deposition process has been used. In this study, a new plasma process to solve the cross-contamination problem in a single-chamber PECVD system was suggested. A single-chamber VHF-PECVD system was used for superstrate type p-i-n a-Si:H solar cell manufacturing on Asahi-type U FTO glass. A 80 MHz and 20 watts of pulsed RF power was applied to the parallel plate RF cathode at the frequency of 10 kHz and 80% duty ratio. A mixture gas of Ar, H2 and SiH4 was used for i-layer deposition and the deposition pressure was 0.4 Torr. For p and n layer deposition, B2H6 and PH3 was used as doping gas, respectively. The deposition temperature was $250^{\circ}C$ and the total p-i-n layer thickness was about $3500{\AA}$. In order to remove the deposited B inside of the vacuum chamber during p-layer deposition, a high pulsed RF power of about 80 W was applied right after p-layer deposition without SiH4 gas, which is followed by i-layer and n-layer deposition. Finally, Ag was deposited as top electrode. The best initial solar cell efficiency of 9.5 % for test cell area of 0.2 $cm^2$ could be achieved by applying the in-situ plasma cleaning method. The dependence on RF power and treatment time was investigated along with the SIMS analysis of the p-i interface for boron profiles.

• 열처리공학회지
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• 제5권1호
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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.