• 한국정보디스플레이학회:학술대회논문집
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• 한국정보디스플레이학회 2002년도 International Meeting on Information Display
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• pp.224-227
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• 2002

The relationship between the discharge aging time and the superficial layer thickness of MgO thin film was investigated in an AC PDP. The discharge characteristics of an AC PDP with the various aging time were evaluated by discharge aging experiments. We find the presence of a superficial lay which is related to the discharge characteristics during aging process. The superficial layer of MgO thin film was observed by Transmission Electron Microscope (TEM). It was found that the superficial layer thickness of MgO was dependent on discharge aging time.

• Corrosion Science and Technology
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• 제17권2호
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• pp.54-59
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• 2018

The effect of external DC electric field on atmospheric corrosion behavior of zinc under a thin electrolyte layer (TEL) was investigated by measuring open circuit potential (OCP), cathodic polarization curve, and electrochemical impedance spectroscopy (EIS). Results of OCP vs. time curves indicated that the application of external DC electric field resulted in a negative shift of OCP of zinc. Results of cathodic polarization curves measurement and EIS measurement showed that the reduction current of oxygen increased while charge transfer resistance ($R_{ct}$) decreased under the external DC electric field. Variation of OCP negative shift, reduction current of oxygen, and $R_{ct}$ increase with increasing of external DC electric field strength as well as the effect of external DC electric field on double-layer structure in the electrode/electrolyte interface and ions distribution in thin electrolyte layer were analyzed. All results showed that the external DC electric field could accelerate the corrosion of zinc under a thin electrolyte layer.

• 대한기계학회논문집B
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• 제23권3호
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• pp.311-319
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• 1999

The thermal conductivity ${\lambda}_b$, thermal diffusivity ${\alpha}_b$ of the thin black paint layer sprayed on solid surface and absorptivity a for laser beam are measured by applying a non-contact measurement method of the thermophysical properties of solids. The values of a=0.67, ${\lambda}_b=1.45W/mK$ and ${\alpha}_b=1.24{\times}10^{-6}m^2/s$ are obtained for the sprayed lay~ thickness $z_b{\fallingdotseq}40\;{\mu}m$. Furthermore, for the $z_b{\fallingdotseq}24\;{\mu}m$ thick layers which arc formed by rubbing with a glass rod after spraying, the values of a=0.73, ${\lambda}_b=1.85W/mK$. and ${\alpha}_b=1.09{\times}10^{-6}m^2/s$ are obtained. It is also shown that the present thermal diffusivity ${\alpha}_b$ for $z_b{\fallingdotseq}40\;{\mu}m$ Is about 30~80% larger than those obtained by Araki et al. for the thicker layer $z_b{\fallingdotseq}150{\sim}248\;{\mu}m$. This method could be applied to the measurement of thermophysical properties of thin layer on solids.

• 한국재료학회지
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• 제23권9호
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• pp.495-500
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• 2013

Mo-based thin films are frequently used as back electrode materials because of their low resistivity and high crystallinity in CIGS chalcopyrite solar cells. Mo:Na/Mo bilayer thin films with $1{\mu}m$ thickness were deposited on soda lime glass by varying the thickness of each layer using dc-magnetron sputtering. The effects of the Mo:Na layer on morphology and electrical property in terms of resistivity were systematically investigated. The resistivity increased from $159{\mu}{\Omega}cm$ to $944{\mu}{\Omega}cm$; this seemed to be caused by increased surface defects and low crystallinity as the thickness of Mo:Na layer increased from 100 nm to 500 nm. The surface morphologies of the Mo thin films changed from a somewhat coarse fibrous structures to irregular and fine celled structures with increased surface cracks along the cell boundaries as the thickness of Mo:Na layer increased. Na contents varied drastically from 0.03 % to 0.52 % according to the variation of Mo:Na layer thickness. The change in Na content may be ascribed to changes in surface morphology and crystallinity of the thin films.

• 한국진공학회:학술대회논문집
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• 한국진공학회 2012년도 제42회 동계 정기 학술대회 초록집
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• pp.252-252
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• 2012

It is widely accepted that short exciton diffusion lengths of organic semiconductors with respect to the film thickness limit the charge (hole and electron) separation before excitons recombination in organic photovoltaic (OPV) cells. Therefore the efficient absorption of incident light within the thin active organic layer is of great importance to improve the power conversion efficiency (PCE) of the cells. In this work, we fabricated 2-dimensionally (2D) nano-patterned poly(3,4-ethylenedioxythiophene): poly(styrenesulfonate) (PEDOST:PSS) layers using capillary phenomenon and nano-imprinting technology at the scale of several hundred nanometers. This 2D nano-patterned PEDOT:PSS layer exerted photonic crystal effect such as redirection of light paths and variation of light intensity at specified wavelengths. It is also expected that the consequently alternated light pass lengths and intensities change the absorption properties of zinc phthalocyanine (ZnPc) thin films grown on top of the nano-patterned PEDOT:PSS layer. The influence of conductivity and thickness of the PEDOT:PSS layer on the absorption properties of ZnPc thin films were also investigated.

• 정보저장시스템학회논문집
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• 제2권1호
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• pp.85-90
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• 2006

In this study, measurement of thermal conductivity of multilayer thin dielectric film has been conducted via differential $3\omega$ method. Also, verification of differential $3\omega$ method has been accomplished with various proposed criteria. The target film for the measurement is 300 nm thick silicon dioxide which is covered with upper protective layer of various thicknesses. The upper protective layer is inserted between the target film and the heater line for purpose of electrical insulator or anti-oxidation barrier since the target film may be a good electrical conductor or a well-oxidizing material. Since the verification of differential $3\omega$ method has not been conducted yet, we have shown that the measurement of thermal conductivity of thin films with upper protective layer via differential $3\omega$ method is verified to be reliable as long as the proposed preconditions of the samples are satisfied. Experimental results show that the experimental errors tend to increase with aspect ratio between thickness of the upper protective layer and width of the heater line due to heat spreading effect.

• Current Photovoltaic Research
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• 제2권1호
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• pp.1-7
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• 2014

We developed a method of growing thin Si film at $600^{\circ}C$ by hot wire CVD using a very thin large-grained poly-Si seed layer for thin-film Si solar cells. The seed layer was prepared by crystallizing an amorphous Si film by vapor-induced crystallization using $AlCl_3$ vapor. The average grain size of the p-type epitaxial Si layer was about $20{\mu}m$ and crystallographic defects in the epitaxial layer were mainly low-angle grain boundaries and coincident-site lattice boundaries, which are special boundaries with less electrical activity. Moreover, with a decreasing in-situ boron doping time, the mis-orientation angle between grain boundaries and in-grain defects in epitaxial Si decreased. Due to fewer defects, the epitaxial Si film was high quality evidenced from Raman and TEM analysis. The highest mobility of $360cm^2/V{\cdot}s$ was achieved by decreasing the in-situ boron doping time. The performance of our preliminary thin-film solar cells with a single-side HIT structure and $CoSi_2$ back contact was poor. However, the result showed that the epitaxial Si film has considerable potential for improved performance with a reduced boron doping concentration.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2001년도 추계학술대회 논문집 Vol.14 No.1
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• pp.281-283
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• 2001

$Bi_{2}Sr_{2}CuO_{x}$(Bi-2201) thin films were fabricated by atomic layer-by-layer deposition using an ion bearn sputtering method. 10 wt% and 90 wt% ozone mixed with oxygen were used with ultraviolet light irradiation to assist oxidation. At early stages of the atomic layer by layer deposition. two dimensional epitaxial growth which covers the substrate surface would be suppressed by the stress and strain caused by the lattice misfit. then three dimensional growth takes place. Since Cu element is the most difficult to oxidize. only Sr and Bi react with each other predominantly. and forms a buffer layer on the substrate in an amorphous-like structure. which is changed to $SrBi_{2}O_{4}$ by in-situ anneal.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2001년도 추계학술대회 논문집
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• pp.281-283
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• 2001

Bi$_2$Sr$_2$CuO$\_$x/(Bi-2201) thin films were fabricated layer-by-layer deposition using an ion beam sputtering method. 10 wt% and 90 wt% ozone mixed with oxygen were used ultraviolet light irradiation to assist oxidation. At early stages of the atomic layer by layer deposition, two dimensional epitaxial growth which covers the substrate surface would be suppressed by the stress and strain caused by the lattice misfit, then three dimensional growth takes place. Since Cu element is the most difficult to oxidize, only Sr and Bi react with each other predominantly, and forms a buffer layer on the substrate in an amorphous-like structure, which is changed to SrBi$_2$O$_4$ by in-situ anneal.

• Journal of Electrical Engineering and Technology
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• 제6권6호
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• pp.836-841
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• 2011

Plasma polymerized methyl methacrylate (ppMMA) thin films were deposited by plasma polymerization technique with different plasma powers and subsequently thermally treated at temperatures of 60 to $150^{\circ}C$. To find a better ppMMA preparation technique for application to organic thin film transistor (OTFT) as dielectric layer, the chemical composition, surface morphology, and electrical properties of ppMMA were investigated. The effect of ppMMA thin-film preparation conditions on the resulting thin film properties were discussed, specifically O-H site content in the pMMA, dielectric constant, leakage current density, and hysteresis.