• 대한전자공학회논문지
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• 제21권6호
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• pp.64-69
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• 1984

Al-MIS(p-Si)태양전지의 최대 효율은 Al 박막을 0.6A/sec 이하의 속도로 증착시켜 80Å인 두께가 되었을 때임을 알았다. ZnS와 SiO로 AR coating을 했는데, 단층 피막일때는 각각 570Å과 690Å인 박막 두께에서 최대 Isc를 나타냈다. 이는 quarter-coating 조건인 n1d1=λ/4를 만족함을 알았다. 이중층 피막일 때는 한 층을 단층 피막때의 최적 두께를 유지하면서 다른 한 층을 조절했다. 이때의 최대 Isc는 단층피막일 때와 비슷한 값이었으나 넓은 범위의 두께에서 그 값이 그대로 유지되었다. 한편 dzns/ds10=1.9/2.3=570/690인 관계를 유지하면서 총 두께를 각각의 단층피막때의 최적 두께 합에 대해서 70∼90%로 얇게 했을 때 앞에서 논의한 어떤 경우보다도 20%이상의 더 높은 Isc를 얻을 수 있었다 따라서 높은 효율을 얻으면서 정밀한 두께 조절이 불필요한 새로운 AR coating방법을 얻었다.

• 유체기계공업학회:학술대회논문집
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• 유체기계공업학회 2005년도 연구개발 발표회 논문집
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• pp.693-697
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• 2005

• 펄프종이기술
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• 제35권3호
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• pp.21-28
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• 2003

It is essential to use base papers having proper surface characteristics in coating operation for improving coated paper quality and coater runnability. To fulfill these purposes surface sizing of coating base stock with anionic oxidized starch is commonly practiced. It is suggested that use of cationic starch for surface sizing rather than conventional oxidized starch will improve coated paper quality since cationic starch penetrates less into paper structure because of its strong electrostatic interaction with anionically charged paper surface. Strong interaction of cationic surface sizing starch with anionic coating color is expected to promote rapid immobilization of the coating color and improve coating holdout and optical property. The immediate objective of this study was to examine the influence of surface sizing starches on the properties of coated papers. Structural characteristics of the coatings formed on the substrate surface sized with cationic and anionic starches were examined. To enhance the efficiency of cationic surface sizing starch on coated paper properties, strongly charged cationic polymers were added to the surface sizing starch and its effect on coated paper properties was evaluated. Results showed that opacity and light scattering coefficient of coated paper were higher when base paper surface sized with cationic starch was used. Addition of less than 1% of cationic poly-DADMAC to the cationic surface sizing starch improved the opacity of coated paper significantly.

• 한국수소및신에너지학회논문집
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• 제20권4호
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• pp.323-330
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• 2009

Efficiency of a fuel cell is determined by the generated water. If water is not removed sufficiently, water will be accumulated at GDL, which causes flooding. Therefore, water control is regarded as a crucial factor to sustain fuel ell performance. In this study, PTFE coating on the surface of carbon paper was carried out to establish optimum process for hydrophobic treatment of GDL. Carbon paper was immersed at different concentrations of nano-sized PTFE coating solution. Their characteristics were analyzed systematically by FE-SEM, water contact angle, cyclic voltamogam, XRD and FT-IR. The quantitative correlation between the amount of coated-PTFE on a carbon paper and concentration of coating solution was carefully investigated. It is suggested that the amount of PTFE-coating on a carbon paper can be managed by means of controling concentration of coating solution.

• International Journal of Naval Architecture and Ocean Engineering
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• 제3권4호
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• pp.242-253
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• 2011

Skin frictional drag reduction efficiency of "stiff" compliant coating was investigated in a wind tunnel experiment. Flat plate compliant coating inserts were installed in a wind tunnel and the measurements of skin frictional drag and velocity field were carried out. The compliant coatings with varying viscoelastic properties had been prepared using different composition. In order to optimize the coating thickness, the most important design parameter, the dynamic viscoelastic properties had been determined experimentally. The aging of the materials (variation of their properties) during half a year was documented as well. A design procedure proposed by Kulik et al. (2008) was applied to get an optimal value for the coating thickness. Along with the drag measurement using the strain balance, velocity and pressure were measured for different coatings. The compliant coatings with the thickness h = 7mm achieved 4~5% drag reduction within a velocity range 30~40 m/s. The drag reduction mechanism of the attenuation of turbulence velocity fluctuations due to the compliant coating was demonstrated. It is envisioned that larger drag reduction effect is obtainable at higher flow velocities for high speed trains and subsonic aircrafts.

• 반도체디스플레이기술학회지
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• 제19권3호
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• pp.30-35
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• 2020

A microlens has been fabricated by various methods such as a thermal reflow, hot embossing, diamond milling, etc. However, these methods require a relatively complex process to control the microlens shape. In this work, we report on a simple and cost-effective method to fabricate a cylindrical microlens (CML), which can diffuse light widely. We have employed a slot-die head with the dual plate (a meniscus guide with a protruded μ-tip and a shim with a slit channel) for coating of a narrow stripe using poly(methyl methacrylate) (PMMA). We have shown that the higher the coating gap, the lower the maximum coating speed, which causes an increase in the stripe width and thickness. The coated PMMA stripe has the concave shape. To make it in the shape of a convex microlens, we have applied the thermal reflow method. When the stripe thickness is small, however, its effect is negligible. To increase the stripe thickness, we have increased the number of repeated coating. With this scheme, we have fabricated the CML with the width of 223 ㎛ and the thickness of 7.3 ㎛. Finally, we have demonstrated experimentally that the CML can diffuse light widely, a feature demanded for light extraction efficiency of organic light-emitting diodes (OLEDs) and suppression of moiré patterns in displays.

• 한국산학기술학회논문지
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• 제14권9호
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• pp.4467-4471
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• 2013

본 연구에서는 Nano급 반도체 생산공정에서 필수적인 스피너(spinner) 설비의 감광액 도포(photo resist coating)시스템의 효율을 획기적으로 개선할 수 있는 새로운 완전스캔(Full-scan) 방식의 감광액 도포시스템(FPCS : Full-scan Photo-resist Coating System)을 개발하였다. 또한, 감광액의 미 도포로 인한 복합적인 공정불량을 예방하기 위하여 실시간(real-time)으로 상태요소들을 감시할 뿐만 아니라 상태요소의 비정상적 변화나 웨이퍼 가공불량이 발생할 경우 해당 유니트(unit)를 정지시킴과 동시에 원격지에 있는 엔지니어에게 경보를 전송함으로써 즉각적인 대처가 가능할 수 있도록 개발하였다.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2007년도 하계학술대회 논문집 Vol.8
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• pp.424-425
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• 2007

Anti-Reflection and High-reflection coating on the facet of semiconductor laser diode. To prevent internal feedback from both facets for realizing super luminescent diode and reducing the reflection-induced intensity noise of laser diode. Anti-Reflection coating Film was designed by Macleod Simulator. Coating Materials were decided $Ti_3O_5$ and $SiO_2$. Thickness of Coating layer $Ti_3O_5/SiO_2$ were 105[nm], 165[nm]. In the study Anti-Reflection coating Film was design for Laser diode and deposited by Ion-Assisted Deposition system. Then manufactured thin film measured electrical properties(L-I-V, Se, Resistor) and Optical properties(wavelength FFP). Slop-efficiency and FFP characteristic is 0.302[W/A], $22.3^{\circ}$(Horizontal), $24.4^{\circ}$(Vertical).

• 한국산학기술학회논문지
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• 제12권11호
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• pp.5172-5177
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• 2011

본 논문은 박막 실리콘 태양전지에 적용되는 반사방지 또는 고반사 코팅 기술에 관한 연구이다. 태양광 흡수율을 개선하기 위하여 박막 실리콘 태양전지의 앞면에는 반사를 줄이는 반사방지막 기술이 필요하며, 뒷면에는 반대로 반사를 높이는 고반사 기술이 필요하다. 반사방지막 기술에서 단층의 구조에서는 코팅의 두께에 따라 반사율이 틀려지고, 적절한 범위에서 두께를 제어하면 낮은 반사율을 얻을 수 있다. 대칭형태의 다층의 구조에서는 단층구조에 비해서 넓은 파장대에 걸쳐서 낮은 반사율을 얻을 수 있다. 또한 뒷면에 적용되는 고반사막 기술에서는 높은 굴절율을 갖는 매질과 낮은 굴절율을 갖는 매질을 대칭 구조로 구성하여 계산한 결과 높은 반사율을 얻을 수 있다는 것을 확인하였다.

• 한국분말재료학회지
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• 제28권3호
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• pp.233-238
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• 2021

Iron-based amorphous powder attracts increasing attention because of its excellent soft magnetic properties and low iron loss at high frequencies. The development of an insulating layer on the surface of the amorphous soft magnetic powder is important for minimizing the eddy current loss and enhancing the energy efficiency of high-frequency devices by further increasing the electrical resistivity of the cores. In this study, a hybrid insulating coating layer is investigated to compensate for the limitations of monolithic organic or inorganic coating layers. Fe₂O₃ nanoparticles are added to the flexible silicon-based epoxy layer to prevent magnetic dilution; in addition TiO₂ nanoparticles are added to enhance the mechanical durability of the coating layer. In the hybrid coating layer with optimal composition, the decrease in magnetic permeability and saturation magnetization is suppressed.