• Journal of the Korean Ceramic Society
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• v.41 no.5
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• pp.364-369
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• 2004

The barrier and optical properties of AlO$_{x}$ thin films on polycarbonate deposited by Reactive Ion Beam Sputtering (RIBS) were investigated at different oxygen partial pressure. We measured the deposition rate of AlO$_{x}$ thin films. As the oxygen partial pres-sure increased, the deposition rate increased then decreased. The changes of deposition rate are associated with the properties of deposited films. The properties of deposited AlO$_{x}$ thin films were studied using X-ray Photoelectron Spectroscopy (XPS), Scan-ning Electron Microscopy (SEM), and Atomic Force Microscopy (AFM). Optimum deposition parameters were found for fabricat-ing aluminum oxide thin films with high optical transparency for visible light and low Oxygen Transmission Rate (OTR). The optical transmittance of AlO$_{x}$ thin film deposited on polycarbonate (PC) showed the same value of bare PC.bare PC.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.66 no.8
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• pp.1236-1241
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• 2017

We deposited Al-doped ZnO (ZnO:Al) thin films on glass substrates ($200mm{\times}200mm$) by using in-line magnetron sputtering system. Effects of various deposition parameters such as working pressure, deposition power and substrate temperature on optoelectronic characteristics including surface-texture etching profiles were carefully investigated in this study. We found that relatively low working pressure and high deposition power offered to obtain enhanced conductivity and optical transmittance. Haze properties showed similar trend with the transmittance. Furthermore, surface-texture etching study exhibited good morphologies when the films were deposited at $200-300^{\circ}C$. On the basis of these optimizations, we could find the deposition region that produces highly transparent and conductive properties including efficient light scattering capability.

• Journal of the Korean Ceramic Society
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• v.23 no.5
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• pp.81-85
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• 1986

$SnO_2$ thin films have been prepared by chemical vapor deposition technique. Electrical and optical properties of the films have been investigated. It is found that the electrical condictivity and optical transparency of the films are most affected by deposition temperature and more affected by $SnCl_4$ partial pressure than by $O_2$ partial pressure. Experimental results show that the conductivity increases with high optical transparency as deposition temperature increases up to 50$0^{\circ}C$ but the conductivity decreases with the loss of transparency as deposition temperature increases above $600^{\circ}C$.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2000.11a
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• pp.471-475
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• 2000

P-type (100) Si wafer patterned with 1000$\AA$ SiO$_2$island was used as substrate and the Si films were deposited under low pressure using Si$_2$H$_{6}$-H$_2$gas mixture where the total gas flow rate and deposition pressure were 16.6sccm and 3.5mtorr, respectively. In this condition, we selectively obtained high-quality epitaxial Si layer of the 350~1050$\AA$ thickness. In order to extend the incubation period, we kept high pressure H$_2$ environment without Si$_2$H$_{6}$ gas for few minutes after first incubation period and then we conformed the existence of second incubation period.iod.

• Carbon letters
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• v.13 no.4
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• pp.205-211
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• 2012

Methanol as a carbon source in chemical vapor deposition (CVD) graphene has an advantage over methane and hydrogen in that we can avoid optimizing an etching reagent condition. Since methanol itself can easily decompose into hydrocarbon and water (an etching reagent) at high temperatures [1], the pressure and the temperature of methanol are the only parameters we have to handle. In this study, synthetic conditions for highly crystalline and large area graphene have been optimized by adjusting pressure and temperature; the effect of each parameter was analyzed systematically by Raman, scanning electron microscope, transmission electron microscope, atomic force microscope, four-point-probe measurement, and UV-Vis. Defect density of graphene, represented by D/G ratio in Raman, decreased with increasing temperature and decreasing pressure; it negatively affected electrical conductivity. From our process and various analyses, methanol CVD growth for graphene has been found to be a safe, cheap, easy, and simple method to produce high quality, large area, and continuous graphene films.

• Journal of the Korean institute of surface engineering
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• v.29 no.5
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• pp.498-504
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• 1996

The synthesis of carbon nitride thin films with high nitrgen concentration was accomplished by reactive supttering at relatively high working pressure. In conventional reactive sputter-deposition of carbon nitride films, working pressure was 0.3-5Pa and the ratio of nitrogen to carbon(N/C ratio) in the films was less than 0.5. In this study, amorphous carbon nitride films with the N/C ratio $\tickapprox$ 1.0 were prepared on Si(100). substrates at higher pressure, 20-60 Pa. Structural analyses with Fourier transform infrared spectroscopy and X-ray photoelectron spectroscopy revealed that the films prepared consisted of triazine-like plain network.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.17 no.12
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• pp.1301-1307
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• 2004

Reduced pressure chemical vapor deposition(RPCYD) technology has been investigated for the growth of SiGe epitaxial films with two dimensional in-situ doped boron impurities. The two dimensional $\delta$-doped impurities can supply high mobility carriers into the channel of SiGe heterostructure MOSFETs(HMOS). Process parameters including substrate temperature, flow rate of dopant gas, and structure of epitaxial layers presented significant influence on the shape of two dimensional dopant distribution. Weak bonds of germanium hydrides could promote high incorporation efficiency of boron atoms on film surface. Meanwhile the negligible diffusion coefficient in SiGe prohibits the dispersion of boron atoms: that is, very sharp, well defined two-dimensional doping could be obtained within a few atomic layers. Peak concentration and full-width-at-half-maximum of boron profiles in SiGe could be achieved in the range of 10$^{18}$ -10$^{20}$ cm$^{-3}$ and below 5 nm, respectively. These experimental results suggest that the present method is particularly suitable for HMOS devices requiring a high-precision channel for superior performance in terms of operation speed and noise levels to the present conventional CMOS technology.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2003.05a
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• pp.30-33
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• 2003

YBCO coated conductor, also called the 2nd generation high temperature superconducting wire, consists of oxide multi-layer hetero-epitaxial thin films. Pulsed laser deposition (PLD) is one of many film deposition methods used to make coated conductor, and is the one known to be the best to make superconducting layer so far. As a part of the effort to make long length coated conductor, the optimum deposition condition of YBCO film on single crystal substrate (SrTiO3) was investigated using PLD. Substrate temperature, oxygen partial pressure, and laser fluence were varied to find the best combination to grow high quality YBCO film.

• Journal of the Korean institute of surface engineering
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• v.33 no.2
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• pp.69-76
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• 2000

The rf plasma chemical vapor deposition is a common method employed for diamond or amorphous carbon deposition. Diamond possesses the strongest bonding, as exemplified by a number of unique properties-extraordinary hardness, high thermal conductivity, and a high melting tempera tore. Therefore, it is very important to investigate the synthesis of semiconducting diamond and its use as semiconductor devices. An inductively coupled rf plasma CVD system for producing amorphous carbon films were developed. Uniform temperature and concentration profiles are requisites for the deposition of high quality large-area films. The system consists of rf matching network, deposition chamber, pumping lines for gas system. Gas mixtures with methane, and hydrogen have been used and Si (100) wafers used as a substrate. Amorphous carbon films were deposited with methane concentration of 1.5% at the process pressure of S torr~20 torr, and process temperature of about $750^{\circ}C$. The nucleation and growth of the amorphous carbon films have been characterized by several methods such as SEM and XRD.

• Journal of the Korean Ceramic Society
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• v.53 no.6
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• pp.647-651
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• 2016

SiC films were prepared on glassy carbon substrates by laser chemical vapor deposition under a high pressure of $10^4Pa$ using a diode laser (wavelength = 808 nm) and a polysilaethylene precursor. (111)-oriented SiC films were formed at a deposition temperature ($T_{dep}$) range of 1150 - 1422 K. At $T_{dep}=1262K$, the SiC film with a high Lotgering factor of above 0.96 showed an exhibited pyramid-like surface morphology and flower-like grains. The highest deposition rate ($R_{dep}$) was $220{\mu}m\;h^{-1}$ at $T_{dep}=1262K$.