• Journal of the Semiconductor & Display Technology
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• v.8 no.2
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• pp.11-14
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• 2009

The $Sr_{0.7}Bi_{2.3}Nb_2O_9$(SBN) thin films are deposited on Pt-coated electrode(Pt/Ti/$SiO_2$/Si) using RF sputtering method at various $Ar/O_2$ ratio. We investigated the effect of deposition condition(specially $Ar/O_2$ ratio) on the structural properties of SBN thin film. As $Ar/O_2$ ratio was increased, the peaks in the XRD pattern became more sharp. Also, the peaks(008)(115)(220) in 80/20 of $Ar/O_2$ ratio were suddenly appeared. The optimum of the rougness showed about 4.33 nm in 70/30 of $Ar/O_2$ ratio. The crystallinity of SBN thin films were increased with the increase of $Ar/O_2$ ratio. Also, Deposition rate of SBN thin films was about 4.17 nm/min in 70/30 of $Ar/O_2$ ratio. The capacitance of SBN thin films were increased with the increase of $Ar/O_2$ ratio.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2007.06a
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• pp.517-520
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• 2007

The BSCCO thin film fabricated by using the layer by layer deposition method was compared with the BSCCO thin film fabricated by using the evaporation method. Reevaporation in the form of Bi atoms or $Bi_2O_3$molecules easily bring out the deficiency of Bi atoms in thin film due to the long sputtering time of the layer by layer deposition. On the other hand, the respective atom numbers corresponding to BSCCO phase is concurrently supplied on the film surface in the evaporation deposition process and leads to BSCCO phase formation. Also, it is cofirmed that by optimizing the deposition condition, each single phase of the Bi2201 phase and the Bi2212 phase can be fabricated, the sticking coefficient of Bi element is clearly related to the changing of substrate temperature and the formation of the Bi2212 phase.

• Journal of the Korean institute of surface engineering
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• v.41 no.1
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• pp.6-11
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• 2008

An Indium Zinc Oxide(IZO) transparent conductive layer was deposited on a large size glass substrate by using magnetron dc sputtering method with varying a deposition temperature. As the deposition temperature decreased to a room temperature, the sheet resistance of IZO film increased. But this deposition temperature range is included in an applicable to a device. From a standpoint of the sheet resistance, the differences of the sheet resistance were not great and the uniformity of the layer was uniformed around 10%. Crystallization particles were shown on the surface of the layer as deposition temperature increased, but these particles were not shown on the surface of the layer as deposition temperature decreased to the room temperature. It didn't make a scrap of difference in a transmittance of varying deposition temperature. Therefore, it is concluded that IZO thin film manufactured by the room temperature deposition condition can be used as a large size transparent conductive layer of a liquid crystal display device.

• Journal of the Korean Ceramic Society
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• v.28 no.10
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• pp.777-784
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• 1991

Diamond films have been growth by the hot-filament chemical vapor deposition (HFCVD) using CH4 and H2 gaseous mixture on the Si substrate. The experimental results indicated that the deposits were pure diamond and contained no amount of non-diamond phases such as amorphous carbon or graphite. The diamond films were deposited well at the conditions: the filament temperature of 210$0^{\circ}C$, the substrate temperature of 77$0^{\circ}C$, the CH4 concentration of 1.76%, the reactor pressure of 30 torr, and the deposition time of 7 hr. At this growth condition, the maximum deposition rate was 2 ${\mu}{\textrm}{m}$/hr. X-ray diffraction patterns and texture coefficient results showed that preferred orientation of the diamond films was {111} orientation under all experimental conditions.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2001.07a
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• pp.362-364
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• 2001

The pulsed laser deposition(PLD) technology was used for the deposition of phosphor substance, Gd$_2$O$_3$on commercial glass. An Nd:YAG laser was employed for the deposition (wavelength 266nm, energy up to 100mJ/pu1se, pulse duration is 5ns and repetition rate 10 Hz). With respect to films grown by conventional PLD, this study exhibited the condition at normal temperature. Experiments were done without any reactive gas at a pressure of 10$^{-5}$ ~10$^{-6}$ Torr using second harmonic(λ=532 nm) and fourth harmonic(λ=266 nm) Nd:YAG laser. Analyses of the deposited material grown are performed by EDX, AFM, SEM, PL meseurements.

• Proceedings of the Korea Institute of Applied Superconductivity and Cryogenics Conference
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• 2003.10a
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• pp.153-156
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• 2003

The multi-layer oxide buffer layer for the coated conductor was deposited on biaxially textured Ni substrates using pulsed laser deposition. Oxygen partial pressure, 4％$H_2$/Ar partial pressure, and deposition temperature were deposition variables investigated to find the optimum deposition conditions. $Y_2$O$_3$seed layer was deposited epitaxially on metal substrate. The full buffer architecture of $Y_2$O$_3$/YSZ/CeO$_2$was successfully prepared on metal substrate.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2000.11a
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• pp.367-370
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• 2000

In this study, thin films of 70/30 and 80/20 mol% P(VDF-TrFE) copolymers were fabricated by physical vapor deposition method. In order to determine the optimum deposition condition, the copolymer thin films were fabricated in the heating temperature of 260$^{\circ}C$, 280$^{\circ}C$, and 300$^{\circ}C$. The deposition rate was measured in a real time by thickness monitor. The surface image of prepared thin films was analyzed by using AFM. From the results of TG-DTA,70/30 and 80/20 mol% P(VDF-TrFE) copolymers were observed the Curie transition point below the melting point. As the results of AFM and FT-IR analysis, we determined that the optimum deposition temperature was 300$^{\circ}C$.

• Applied Chemistry for Engineering
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• v.10 no.1
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• pp.98-104
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• 1999

In this work, we investigated hydrogen content, bond structure, and electrical properties of a-Si:H films prepared by ECR plasma CVD as a function of pressure. In general, the photo sensitivity of a-Si:H films prepared by CVD method decreases as the deposition rate increases, but the photo sensitivity of a-Si:H films prepared by ECR plasma deposition method increases as the deposition rate increases. In the same condition of microwave power, the ratio of $SiH_4/H_2$, and pressure, though film thickness increases linearly with deposition time and hydrogen content in the film is constant, photo conductivity can be decreased because $SiH_2$ bond is made more than SiH bond in the short reaction time. According to increase pressure in the chamber, SiH bond in the film increase and optical energy gap decrease. So, photo conductivity can be increased. But photo sensitivity decreased as dark conductivity increase. It must be grown in the condition of low pressure and hydrogen gas for taking the a-Si:H film of high quality.

• Tunnel and Underground Space
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• v.10 no.2
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• pp.237-248
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• 2000

Based on the preliminary results from the therm analysis, which is currently carrying, three-dimensional computer simulations using a finite element code, ABAQUS Ver. 5.8, were designed to determine the mechanically stable cavern and deposition hole spacing. Linear elastic modeling for the cases with different cavern and deposition hole spacing were carried out under three different in situ stress conditions. From the simulations, the response of the rock to the stress redistribution after the excavation of the openings could be investigated. Also the optimum cavern and deposition hole spacing could be estimated based on the factor of safety. When the in situ stress determined from the actual stress measurements in Korea were used, the case with cavern spacing of 40m and deposition hole spacing of 3m was in very stable condition, because the factor of safety was calculated as 3.42., When the in situ stress conditions for Sweden and Canada were used, the previous case, they seem to be in stable condition, since the factors of safety are still higher than 1.0. From these results, it was concluded that the rock will not fail even after the stress redistribution.

• Progress in Superconductivity
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• v.12 no.1
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• pp.32-35
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• 2010

Potassium doped $BaFe_2As_2$ superconducting thin films by using an ex situ pulsed laser deposition technique were fabricated in various conditions to find out an optimal growth condition. Controlled conditions were annealing temperature, annealing time, and mass of potassium. The $Ba_{1-x}K_xFe_2As_2$ thin films which has most good quality is fabricated at a condition of annealing temperature at $700^{\circ}C$, annealing time of 60 minutes, and 0.6 g of potassium lumps. In this condition we were able to fabricate good quality films with high transition temperature of ~ 39 K.