• 한국정보디스플레이학회:학술대회논문집
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• 2006.08a
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• pp.1779-1783
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• 2006

The hybrid thin-film (HTF) passivation layer composed of the UV curable acrylate layer and MS-31 (MgO:SiO2=3:1wt%) layer was adopted in organic light emitting diode (OLED) to protect organic light emitting materials from penetrations of oxygen and water vapors. The moisture resistance of the deposited HTF layer was measured by the water vapor transmission rate (WVTR). The results showed that the HTF layer possessed a very low WVTR value of lower than $0.007g/m^2$ per day at $37.8^{\circ}C$ and 100% RH. Therefore, the HTF on the OLED was found to be very effective in protect what from the penetrations of oxygen and moisture.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2010.06a
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• pp.196-196
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• 2010

In this work, we deposited SWNTs/silane hybrid thin films by multiple spray-coating on glass substrate, and examined their electrical response for humidity. Generally silane binders which are often used in CNT solution to adhere CNTs to substrate well can be easily functionalized to each own group on the surface of CNTs after they are hardened by way of the hydrolysis reaction. We investigated how silane binders (TEOS,, MTMS and VTMS) in SWNTs hybrid thin films make effect to their electrical response on humidity. As the result, we observed that the resistance in the sample using TEOS was changed dramatically while it was almost invariant in the samples using MTMS and VTMS for increasing humidity.

• 한국정보디스플레이학회:학술대회논문집
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• 2009.10a
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• pp.693-696
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• 2009

The ray-tracing technique was used to optimize the light guide plate for the purpose of improving the on-axis luminance on the edge-lit backlights. One-dimensional prisms and engraved V-shaped patterns were applied to the upper and the lower surfaces of the light guide plate, respectively. By optimizing the apex angles of these micro-structures, as well as the shape of the reverseprism film put over the light guide plate, highly-collimated light-output distribution could be obtained on the backlight, which may contribute to the development of mobile LCD's with low power consumption.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2007.06a
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• pp.551-552
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• 2007

Coating films were prepared from silane-terminated Colloidal silaca(CS) and UV-curable acrylate resin. The silane-terminated CSs were synthesized from CS and methyltrimethoxysilane(MTMS) and then treated with 3-methacryloxypropyltrimethoxysilane(MAPTMS)/3-glycidoxypropyltrimethoxysilane( GPTMS)/vinyltrimethoxysilane(VTMS) by sol-gel process, respectively. The silane-terminated CS and acrylate resin were hybridized using UV-curing system. Thin films of hybrid material were prepared using spin coater on the glass. Their hardness, contact angle and transmittance improved with the addition of silane-terminated CS.

• Journal of Ceramic Processing Research
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• v.13 no.spc1
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• pp.42-46
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• 2012

The effect of the parameters for few-layered graphene growth by thermal CVD on nickel substrate was investigated. Graphene can be synthesized by using different strategies. Chemical vapor deposition (CVD) has known as one of the most attractive methods to produce graphene due to its good film uniformity, compatibility and large scale production. The control of parameters such as temperature, growth time and pressure in CVD process has been widely recognized as the most important process in graphene growth. Different carbon precursors, methane and acetylene, were introduced in the quartz tube with a variety of growth conditions. Raman spectroscopy was used to confirm the presence of a few- or multi-layered graphene.

• Journal of the Microelectronics and Packaging Society
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• v.22 no.4
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• pp.83-89
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• 2015

In this paper, we propose a fabrication technique for enhanced electrical properties of piezoelectric thick films with excellent patterning property using sol-infiltration and a direct-patterning process. To achieve the needs of high-density and direct-patterning at a low sintering temperature (< $850^{\circ}C$), a photosensitive lead zirconate titanate (PZT) solution was infiltrated into a screen-printed thick film. The direct-patterned PZT films were clearly formed on a locally screen-printed thick film, using a photomask and UV light. Because UV light is scattered in the screen-printed thick film of a porous powder-based structure, there are needs to optimize the photosensitive PZT sol infiltration process for obtaining the enhanced properties of PZT thick film. By optimizing the concentration of the photosensitive PZT sol, UV irradiation time, and solvent developing time, the hybrid films prepared with 0.35 M of PZT sol, 4 min of UV irradiation and 15 sec solvent developing time, showed a very dense with a large grain size at a low sintering temperature of $800^{\circ}C$. It also illustrated enhanced electrical properties (remnant polarization, $P_r$, and coercive field, $E_c$). The $P_r$ value was over four times higher than those of the screen-printed films. These films integrated on silicon wafer substrate could give a potential of applications in micro-sensors and -actuators.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2002.11a
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• pp.477-480
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• 2002

Si-O-C(-H) thin film with a tow dielectric constant were deposited on a P-type Si(100) substrate by an inductively coupled plasma chemical vapor deposition (ICPCVD). Bis-trimethylsilymethane (BTMSM, H$_{9}$C$_3$-Si-CH$_2$-Si-C$_3$H$_{9}$) and oxygen gas were used as Precursor. Hybrid type Si-O-C(-H) thin films with organic material have been generated many voids after annealing. Consequently, the Si-O-C(-H) films can be made a low dielectric material by the effect of void. The surface characterization of Si-O-C(-H) thin films were performed by SEM(scanning electron microscope). The characteristic analysis of Si-O-C(-H) thin films were performed by X-ray photoelectron spectroscopy (XPS).

• Proceedings of the Korean Vacuum Society Conference
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• 2016.02a
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• pp.427-427
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• 2016

Organic-inorganic hybrid perovskite have attracted significant attention as a new revolutionary light absorber for photovoltaic device due to its remarkable characteristics such as long charge diffusion lengths (100-1000nm), low recombination rate, and high extinction coefficient. Recently, power conversion efficiency of perovskite solar cell is above 20% that is approached to crystalline silicon solar cells. Planar heterojunction perovskite solar cells have simple device structure and can be fabricated low temperature process due to absence of mesoporous scaffold that should be annealed over 500 oC. However, in the planar structure, controlling perovskite film qualities such as crystallinity and coverage is important for high performances. Those controlling methods in one-step deposition have been reported such as adding additive, solvent-engineering, using anti-solvent, for pin-hole free perovskite layer to reduce shunting paths connecting between electron transport layer and hole transport layer. Here, we studied the effect of alkali metal halide to control the fabrication process of perovskite film. During the morphology determination step, alkali metal halides can affect film morphologies by intercalating with PbI2 layer and reducing $CH3NH3PbI3{\cdot}DMF$ intermediate phase resulting in needle shape morphology. As types of alkali metal ions, the diverse grain sizes of film were observed due to different crystallization rate depending on the size of alkali metal ions. The pin-hole free perovskite film was obtained with this method, and the resulting perovskite solar cells showed higher performance as > 10% of power conversion efficiency in large size perovskite solar cell as $5{\times}5cm$. X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), and inductively coupled plasma optical emission spectrometry (ICP-OES) are analyzed to prove the mechanism of perovskite film formation with alkali metal halides.

• Tribology and Lubricants
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• v.36 no.4
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• pp.215-231
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• 2020

The paper presents extensive survey and review of experimental and analytical researches on fluid film bearings and squeeze film dampers (SFDs) for turbomachinery available in open literature (major archival international journals) published recently (2018 and 2019 only). Over 60 published research works are reviewed based on the research topics and objectives, the types of bearings, size of bearings, and main design parameters with a brief summary of experiments and/or predictions in each work. Some important findings and general observations about the experimental and/or predictive data are also presented. There are several major trends observed throughout the survey. A large portion of the papers focuses on bearing surface textures and effect of operating and assembly conditions on static and/or dynamic forced performances, as well as bearing surface roughness and wear patterns. Researches on geometry of orifices and recesses in hydrostatic (or hybrid) bearings, as well as bearing system stability predictions using thermohydrodynamic analysis and computational fluid dynamics (CFD), are considered as significant topics. Studies on SFDs mainly focus on experimental identification of force coefficients for various SFD geometries and sealing conditions. Reliable experiments of fluid film bearings and SFDs along with the development of experimentally benchmarked predictive tools enable reinforcement of the path for reliable implementations of the bearing components into high performance rotating machinery operating at extreme and harsh conditions. The extensive list of sources of recent experiments in the available open literature is a welcome addition to the analytical community to gauge the accuracy of predictive tools.

• Textile Coloration and Finishing
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• v.34 no.1
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• pp.68-75
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• 2022

The breathable film refers to a high-functional film that allows gas and water vapor to pass through very fine and sophisticated pores but not liquid. In this research, the breathable film was prepared based on linear low-density polyethylene (LLDPE) and CaCO₃ particles by extrude method. The LLDPE composite film containing CaCO₃ particles had excellent mechanical properties and functionalties. The drawing is a technologically simple and excellent method for improving the mechanical properties of composite films. In this work, the effects of draw ratio on morphology, crystallinity, pore size distribution, mechanical properties, and water vapor permeability of the films were examined. The results revealed that both surface morphology and breathability were affected by the influence of chain orientation and crystal growth with increasing the draw ratio. The mechanical properties were improved with increasing the draw ratio.