• Korean Chemical Engineering Research
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• 제60권1호
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• pp.7-11
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• 2022

고분자전해질 연료전지의(PEMFC)의 제막 과정에서 성능 및 내구성을 위해 건조와 어닐링의 열처리 과정이 필요하다. 본 연구에서는 고분자막 내구성 향상을 위한 최적의 어닐링 온도에 대해 연구하였다. 125~175 ℃ 온도 범위에서 어닐링하였고, 각 어닐링 온도에서 내구성의 기초 자료로 열 안정성 및 수소투과도를 측정하였다. 펜톤 반응과 OCV holding에 의해 전기화학적 내구성을 분석했다. 165 ℃ 어닐링 온도가 열 안정성과 수소투과도 면에서 최적의 온도였다. 펜톤 반응에서 165 ℃에서 어닐링한 막의 불소유출속도가 제일 낮고, OCV holding 실험에서도 165 ℃에서 어닐링한 막의 수명이 제일 길어, 165 ℃가 고분자막의 내구성을 위한 최적의 온도임을 확인했다.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2000년도 추계학술대회 논문집
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• pp.476-479
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• 2000

In this study, mesh-type PECVD system was suggested to minimize the hydrogen concentration. The main structural difference between the triode system and a conventional system is that a mesh was attached to the substrate holding electrode. We investigated several conditions to compare with conventional PECVD. The main effect of mesh was to minimize the substrate damage by ion bombardment and to enhance the surface reaction to induce hydrogen desorption. It was also found that hydrogen concentration decreased but deposition rate increased as increasing applied dias. Applied DC bias enhanced sputtering process. Intense ion bombardment causes the weakly bonded hydrogen or hydrogen-containing species to leave the growing film and increased adatom mobility. Furthermore, addition of hydrogen gas enhance the surface diffusion of adatom. The structural properties of poly-Si films were analyzed by scanning electron microscopy(SEM).

• Bulletin of the Korean Chemical Society
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• 제34권7호
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• pp.2067-2072
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• 2013

Hydrogen ($H_2$) treatment using a two-step $TiO_2$ nanotube (TONT) film was performed under various annealing temperatures from $350^{\circ}C$ to $550^{\circ}C$ and significantly influenced the extent of hydrogen treatment in the film. Compared with pure TONT films, the hydrogen-treated TONT (H:TONT) film showed substantial improvement of material features from structural, optical and electronic aspects. In particular, the extent of enhancement was remarkable with increasing annealing temperature. Light absorption by the H:TONT film extended toward the visible region, which was attributable to the formation of sub-band-gap states between the conduction and valence bands, resulting from oxygen vacancies due to the $H_2$ treatment. This increased donor concentration about 1.5 times higher and improved electrical conductivity of the TONT films. Based on these analyses and results, photoelectrochemical (PEC) performance was evaluated and showed that the H:TONT film prepared at $550^{\circ}C$ exhibited optimal PEC performance. Approximately twice higher photocurrent density of 0.967 $mA/cm^2$ at 0.32 V vs. NHE was achieved for the H:TONT film ($550^{\circ}C$) versus 0.43 $mA/cm^2$ for the pure TONT film. Moreover, the solar-to-hydrogen efficiency (STH, ${\eta}$) of the H:TONT film was 0.95%, whereas a 0.52% STH efficiency was acquired for the TONT film. These results demonstrate that hydrogen treatment of TONT film is a simple and effective tool to enhance PEC performance with modifying the properties of the original material.

• Transactions on Electrical and Electronic Materials
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• 제16권1호
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• pp.34-36
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• 2015

Amorphous SiZnSnO(SZTO) thin film transistors(TFTs) have been fabricated by RF magnetron sputtering process, and they were annealed in air and in wet ambient. The electrical performance and the structure were analyzed by I-V measurement, XPS, AFM, and XRD. The results showed improvement in device performance by wet annealing process compared to air annealing treatment, because free electron was shown to be increased due to reaction of oxygen and hydrogen generating oxygen vacancy. This is understood by the generation of free electrons. We expect the wet annealing process to be a promising candidate to contributing to high electrical performance of oxide thin film transistors for backplane device applications.

• 대한전자공학회논문지SD
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• 제46권12호
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• pp.18-23
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• 2009

본 연구는 실리콘 기판과 실리콘 산화막 사이의 계면 트랩 밀도와 게이트 누설 전류를 조사하여, Metal-Oxide-Nitride-Oxide-Silicon (MONOS) 메모리 소자의 계면 트랩 특성의 수소-질소 열처리 효과를 조사하였다. 고속열처리 방법으로 850도에서 30초 동안 열처리한 MONOS 샘플들을 질소 가스와 수소-질소 혼합 가스를 사용하여 450도에서 30분 동안추가 퍼니스 열처리 공정을 수행하였다. 열처리 하지 않은 것, 질소, 수소-질소로 열처리 한 세 개의 샘플 중에서, 커패시터-전압 측정 결과로부터 수소-질소 열처리 샘플들이 가장 적은 계면 트랩 밀도를 갖는 것을 확인하였다. 또한, 전류-전압 측정 결과에서, 수소-질소 열처리 소자의 누설전류 특성이 개선되었다. 위의 실험 결과로부터, 수소-질소 혼합 가스로 추가 퍼니스 열처리의해 실리콘 기판과 산화막 사이의 계면 트랩 밀도를 상당히 줄일 수 있었다.

• 센서학회지
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• 제21권6호
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• pp.425-428
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• 2012

This paper presents the fabrication and characterization of graphene based hydrogen sensors. Graphene was synthesized by annealing process of Ni/3C-SiC thin films. Graphene was transferred onto oxidized Si substrates for fabrication of chemiresistive type hydrogen sensors. Au electrode on the graphene shows ohmic contact and the resistance is changed with hydrogen concentration. Nanoparticle catalysts of Pd and Pt were decorated. Response factor and response (recovery) time of hydrogen sensors based on the graphene are improved with catalysts. The response factors of pure graphene, Pt and Pd doped graphenes are 0.28, 0.6 and 1.26, respectively, at 50 ppm hydrogen concentration.

• 한국수소및신에너지학회논문집
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• 제5권1호
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• pp.33-39
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• 1994

The changes of hydrogenation properties of $LaNi_5$ by hydrogen charging condition were investigated using the P-C-isotherm curves, DSC(Differential Scanning Calorimetry), GC(Gas Chromatograph), X-ray diffractometer. As a results of static hydrogen charging, the hydrogen storage capacity gradually decreased and the plateau region severly slopped. Most of the degraded properties could be restored by the annealing treatment. The degradation of hydrogen storage capacity was related with the formation of stable hydride, which was not dehydrided at room temperature.

• 한국표면공학회지
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• 제38권1호
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• pp.28-36
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• 2005

In this study, the reflow characteristics of copper thin films which is expected to be used as interconnection materials in the next generation semiconductor devices were investigated. Cu thin films were deposited on the TaN diffusion barrier by metal organic chemical vapor deposition (MOCVD) and annealed at the temperature between 250℃ and 550℃ in various ambient gases. When the Cu thin films were annealed in the hydrogen ambience compared with oxygen ambience, sheet resistance of Cu thin films decreased and the breakdown of TaN diffusion barrier was not occurred and a stable Cu/TaN/Si structure was formed at the annealing temperature of 450℃. In addition, reflow properties of Cu thin films could be enhanced in H₂ ambient. With Cu reflow process, we could fill the trench patterns of 0.16～0.24 11m with aspect ratio of 4.17～6.25 at the annealing temperature of 450℃ in hydrogen ambience. It is expected that Cu reflow process will be applied to fill the deep pattern with ultra fine structure in metallization.

• 한국표면공학회지
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• 제31권2호
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• pp.117-126
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• 1998

In this study, the residue remaining on the silicon wafer during the oxide overetching using $C_4F_8/H_2$ helicon were plasmas and effects of various cleaning and annealing methods on the removal of the remaining residue were investigated. The addition of 30%$H_2$ to the C4F8 plasma increased the C/F ratio and the thickness of the residue on the etched silicon surface. Most of the residuse on the etched surfaces colud be removed by the oxygen plasmsa cleaning followed by thermal annealing over $450^{\circ}C$. Hydrogen-coataining residue formed on the silicon by 70%$C_4F_8/30%H_2$ helicon plasmas was more easily removed than hydrogen-free residue formed residue formed by $C_4F_8$ helicon wear plasmas. However, damage remaining on the silicon surface overetched using 70%$C_4F_8/30%H_2$ helicon plasmas was intensive and the degree of reocvery duing the post-annealing was lower.

• 한국표면공학회지
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• 제52권3호
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• pp.123-129
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• 2019

With recent demand for the renewable energy resources, we conducted a research on the energy conversion and storage device of supercapacitor. The hybrid graphene-zinc oxide(GZO) electrodes for the supercapacitors (SCs) were fabricated and investigated. To increase the electrical conductivity of the GZO electrode, the rapid thermal annealing(RTA) in $Ar/H_2$(10%) atmosphere was applied and the effect was examined by comparing it with RTA at Ar atmosphere. In Raman spectroscopy, the electrodes annealed at 400? in $Ar/H_2$ atmosphere showed a lower ratio of D/G peak than that of annealed at Ar atmosphere, and had a larger specific capacitance(Sc) in the cyclic voltammetry(CV), and a lower the equivalent series resistance(ESR) in the electrochemical impedance spectroscopy(EIS). The reason seems to come from the better mixing of the graphene and zinc oxide by the RTA in $Ar/H_2$(10%).