• 한국표면공학회지
• /
• 제55권6호
• /
• pp.308-318
• /
• 2022

The surface modification and treatment using thermal plasma were reviewed in academic fields. In general, thermal plasma is generated by direct current (DC) and radiofrequency (RF) power sources. Thermal spray coating, a typical commercial process using thermal plasma, is performed by DC thermal plasma, whereas other promising surface modifications have been reported and developed using RF thermal plasma. Beyond the thermal spray coating, physical and chemical surface modifications were attempted widely. Superhydrophobic surface treatment has a very high industrial demand particularly. Besides, RF thermal plasma system for large-area film surface treatment is being developed. Thermal plasma is especially suitable for the surface modification of low-dimensional nanomaterial (e.g., nanotubes) by utilizing high temperature and rapid quenching. It is able to synthesize and modify nanomaterials simultaneously in a one-pot process.

• 마이크로전자및패키징학회지
• /
• 제21권1호
• /
• pp.45-50
• /
• 2014

반도체 미세구리배선 적용을 위하여 구리배선의 습식 표면처리 및 열 사이클에 따른 구리 박막과 실리콘질화막 도포층 사이의 계면접착에너지를 4점굽힘시험을 통해 정량적으로 평가하였다. 구리배선을 화학적 기계적 연마한 후 습식 표면처리를 통하여 구리 박막과 실리콘질화막의 계면접착에너지는 $10.57J/m^2$에서 $14.87J/m^2$로 증가하였다. $-45{\sim}175^{\circ}C$범위에서 250사이클 후, 표면처리를 하지 않은 시편의 계면접착에너지는 $5.64J/m^2$으로, 표면처리를 한 시편은 $7.34J/m^2$으로 감소하였으며, 모든 시편의 박리계면은 구리 박막과 실리콘질화막 계면으로 확인되었다. X-선 광전자 분광법으로 계면 결합 상태를 분석한 결과, 화학적 기계적 연마 공정 후 구리배선의 표면 산화물이 습식표면처리에 의해 효과적으로 제거된 것을 확인하였다. 또한, 열 사이클 처리동안, 구리 박막과 실리콘질화막의 큰 열 팽창 계수 차이로 인한 열응력으로 인하여 구리 박막과 실리콘질화막 계면이 취약해지고, 계면을 통한 산소유입에 따른 구리 산화층이 증가하여 계면접착에너지가 저하된 것으로 판단된다.

• Current Photovoltaic Research
• /
• 제5권3호
• /
• pp.69-74
• /
• 2017

Here we report the influence of thermal treatment on the performance of high efficiency polymer solar cells with the bulk heterojunction films of poly[4,8-bis(5-(2-ethylhexyl)thiophen-2-yl)benzo[1,2-b:4,5-b'] dithiophene-alt-3-fluorothieno[3,4-b]thiophene-2-carboxylate] (PTB7-Th) and [6,6]-phenyl $C_{71}$ butyric acid methyl ester ($PC_{71}BM$). The crystalline nanostructure of PTB7-Th:$PC_{71}BM$ layers, which were annealed at three different temperatures, was investigated by employing synchrotron radiation grazing incidence X-ray diffraction (GIXD) technique. Results showed that the device performance was slightly reduced by thermal annealing at $50^{\circ}C$ but became significantly poor by thermal annealing at $100^{\circ}C$. The poor device performance by thermal annealing was attributed to the collapse in the crystalline nanostructure of PTB7-Th in the PTB7-Th:$PC_{71}BM$ layers as evidenced by the GIXD measurements that exhibited huge reduction in the intensity of PTB7-Th (100) peak even at $50^{\circ}C$.

• Carbon letters
• /
• 제16권1호
• /
• pp.34-40
• /
• 2015

In this study, in order to improve the thermal and electrical properties of epoxy/graphene nanoplatelets (GNPs), surface modifications of GNPs are conducted using silane coupling agents. Three silane coupling agents, i.e. 2-(3,4-epoxycyclohexyl)-ethyltrimethoxysilane (ETMOS), 3-glycidoxypropyltriethoxysilane (GPTS), and 3-glycidoxypropyltrimethoxysilane (GPTMS), were used. Among theses, GPTMS exhibits the best modification performance for fabricating GNP-incorporated epoxy composites. The effect of the silanization is evaluated using transmission electron microscopy (TEM), scanning electron microscopy, thermogravimetric analysis, and energy dispersive X-ray spectroscopy. The electrical and thermal conductivities are characterized. The epoxy/silanized GNPs exhibits higher thermal and electrical properties than the epoxy/raw GNPs due to the improved dispersion state of the GNPs in the epoxy matrix. The TEM microphotographs and Turbiscan data demonstrate that the silane molecules grafted onto the GNP surface improve the GNP dispersion in the epoxy.

• 한국표면공학회지
• /
• 제26권6호
• /
• pp.334-340
• /
• 1993

The physico-chemical properties and characteristics after thermal treatment of natural zeolite from Kampo area were studied. The physico-chemical properties of natural zeolite were studied by investigating chemical composition, x-ray diffraction pattern(XRD), scanning electronic microscope(SEM), infrared spec-tra(IR), thermal analysis(TA), and cation exchange capacity(C.E.C.), and the characteristics of natural zeo-lite after thermal treatment from $400^{\circ}C$ to $900^{\circ}C$ were compared with the natural zeolite. This study showed that clinoptilolite was the predominant costituent in natural zeolite, and the natural zeolite contained a little amount of quartz and feldspar as impurities. Zeolite mineral was seen to develop slowly by the natural alternation of volcanic ash considering the almost amorphous crystal structure. The more temperature of ther-mal treatment increased, the more adsorption capacity decreased, considering the fact that the hydroxy peak diminished on infrared spectra, and that cation exchange capacity also decreased distinctly.

• 접착 및 계면
• /
• 제14권3호
• /
• pp.146-159
• /
• 2013

본 연구에서는 $350^{\circ}C$에서 4 min 이내로 빠르게 등온 안정화공정을 통해 얻어진 레이온직물의 화학조성, 물리적 특성, X-선 회절 패턴, 열안정성 그리고 직물 형상에 미치는 초음파세척 및 화학전처리의 영향을 조사하였다. 안정화공정 동안 레이온직물에서 발생하는 중량감소와 열수축을 줄이고 안정화반응을 촉진시키기 위하여 안정화공정 전에 레이온직물을 먼저 초음파 세척하고 $NH_4Cl$, $Na_3PO_4$, $H_3PO_4$ 및 $ZnCl_2$로 화학전처리 공정을 수행하였다. 결과는 초음파세척 및 화학전처리가 안정화된 레이온직물의 중량감소, 열수축, 미세구조 변화, 탄소함량, 열안정성, 및 직물 형상에 영향을 주었으며, 사용한 안정화시간과 화학전처리제의 종류에 의존하였다.

• 열처리공학회지
• /
• 제23권2호
• /
• pp.83-89
• /
• 2010

Diamond-like carbon (DLC) coating was studied to be a good tribological problem-solver due to its low friction characteristics and high hardness. However, generally hydrogenated DLC film has shown a weak thermal stability above $300^{\circ}C$. However, the silicon doping DLC process by DC pulse plasma enhanced chemical vapor deposition (PECVD) for the new DLC coating which has a good characterization with thermal stability at high temperature itself has been observed. And we were discussed a process for optimizing silicon content to promote a good thermal stability using various tetramethylsilane (TMS) and methane gas at high-temperature. The chemical compositions of silicon-containing DLC film was analyzed using X-ray photoelectron spectroscopy (XPS) before and after heat treatment. Raman spectrum analysis showed the changed structure on the surface after the high-temperature exposure testing. In particular, the hardness of silicon-containing DLC film showed different values before and after the annealing treatment.

• Nuclear Engineering and Technology
• /
• 제44권1호
• /
• pp.21-32
• /
• 2012

Fluorinated compounds mainly used in the semiconductor industry are potent greenhouse gases. Recently, thermal plasma gas scrubbers have been gradually replacing conventional burn-wet type gas scrubbers which are based on the combustion of fossil fuels because high conversion efficiency and control of byproduct generation are achievable in chemically reactive high temperature thermal plasma. Chemical equilibrium composition at high temperature and numerical analysis on a complex thermal flow in the thermal plasma decomposition system are used to predict the process of thermal decomposition of fluorinated gas. In order to increase economic feasibility of the thermal plasma decomposition process, increase of thermal efficiency of the plasma torch and enhancement of gas mixing between the thermal plasma jet and waste gas are discussed. In addition, noble thermal plasma systems to be applied in the thermal plasma gas treatment are introduced in the present paper.

• Macromolecular Research
• /
• 제14권1호
• /
• pp.38-44
• /
• 2006

Vacuum deposited copper phthalocyanine (CuPc) was placed as a thin interlayer between indium tin oxide (ITO) electrode and a hole transporting layer (HTL) in a multi-layered, organic, light-emitting diode (OLEOs). The well-stacked CuPc layer increased the stability and efficiency of the devices. Thermal annealing after CuPc deposition and magnetic field treatment during CuPc deposition were performed to obtain a stacked-CuPc layer; the former increased the stacking density of the CuPc molecules and the alignment of the CuPc film. Thermal annealing at about 100$^{circ}C$ increased the current flow through the CuPc layer by over 25$\%$. Surface roughness decreased from 4.12 to 3.65 nm and spikes were lowered at the film surface as well. However, magnetic field treatment during deposition was less effective than thermal treatment. Eventually, a higher luminescence at a given voltage was obtained when a thermally-annealed CuPc layer was placed in the present, multi-layered, ITO/CuPc/NPD/Alq3/LiF/AI devices. Thermal annealing at about 100$^{circ}C$ for 3 h produced the most efficient, multi-layered EL devices in the present study.

• Carbon letters
• /
• 제15권4호
• /
• pp.247-254
• /
• 2014

In this work, thermal treatment accompanied with different acid treatments was applied to a commercial coal tar pitch (CTP) to obtain a spinnable precursor pitch for carbon fiber. In the case of thermal treatment only, a relatively high reaction temperature of between $380^{\circ}C$ and $400^{\circ}C$ was required to obtain a softening point (SP) range of $220^{\circ}C-260^{\circ}C$ and many meso-phase particles were created during the application of high reaction temperature. When nitric acid or sulfuric acid treatment was conducted before the thermal treatment, the precursor pitch with a proper SP range could be obtained at reaction temperatures of $280^{\circ}C-300^{\circ}C$, which were about $100^{\circ}C$ lower than those for the case of thermal treatment only. With the acid treatments, the yield and SP of the precursor pitch increased dramatically and the formation of meso-phase was suppressed due to the lower reaction temperatures. Since the precursor pitches with acid and thermal treatment were not spinnable due to the inhomogeneity of properties such as molecular weight distribution and viscosity, the CTP was mixed with ethanol before the consecutive nitric acid and thermal treatments. The precursor pitches with ethanol, nitric acid, and thermal treatments were easily spinnable, and their spinning and carbon fiber properties were compared to those of air blowing and thermal treated CTP.