• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 1998년도 봄 학술발표회논문집(II)
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• pp.627-632
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• 1998

This study deals with the effect on adhesive strength properties of waterproofing and reinforcing layer and mortar or concrete substrate applicated by epoxy resin anticorrosive and bonding materials. Properties of adhesive strength change condition of concrete substrate, temperature, moisture, curing and cleaning and so on. The purpose of this study is that it makes the estimation value of bond strength of concrete wall and epoxy resin layer when coated epoxy resin as anticorrosive materials for durability performance estimation depend on concrete watertightness, and when penetrated epoxy resin for the reinforcement of concrete used the carbon fiber sheet.

• 한국세라믹학회지
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• 제28권10호
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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.

• 한국재료학회:학술대회논문집
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• 한국재료학회 2011년도 추계학술발표대회
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• pp.21.1-21.1
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• 2011

Vertically aligned single-crystal ZnO nanowires have been successfully grown on c-plane sapphire substrate using chemical vapor deposition (CVD) without catalyst. According to growth temperatures, it was changed ZnO growth characteristic. We investigated the effect of substrate temperatures on the growth ZnO films or nanowires on c-plane (0001) sapphire substrates. The ZnO films were acquired at $500^{\circ}C$, whereas the ZnO nanowires were obtained at $600^{\circ}C$, $700^{\circ}C$, and $800^{\circ}C$. The growth behavior diameter and growth rate of ZnO were changed due to different temperature. As a result of analyzing in-plane residual stress by X-ray diffraction, the optimized condition of ZnO nanowires were at $600^{\circ}C$.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2008년도 춘계학술대회 및 기술 세미나 논문집 디스플레이 광소자
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• pp.57-58
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• 2008

Microcrystalline (${\mu}c$) silicon thin films were prepared on glass by plasma-enhanced-chemical-vapor-deposition (PECVD) at various substrate temperature, and dilution ratio of $H_2$ with $SiH_4$. The structural and optical properties of. the ${\mu}c-Si$ thin films were investigated using XRD and UV-VIS spectrophotometer. The ${\mu}c-Si$ thin film with 42 nm grain size was grown at optimal condition of 2.5 Torr, spacing between electrodes of 3cm, deposition time of 3000s, RF power of 200W, substrate temperature of $350^{\circ}C$, $SiH_4$ ($20%SiH_4$+80%He) of 50sccm, and $H_2$ of 100sccm.

• Transactions on Electrical and Electronic Materials
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• 제15권6호
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• pp.344-347
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• 2014

This study was carried out on DLC thin film deposition technology used in infrared optical system production as a method of reducing the shape changes of the molding core and the consequent loss of life. Experiments on the deposition on silicon wafer and tungsten carbide used as a substrate for molding core were conducted at each processing condition using a filtered arc system, and it was found that the surface and mechanical properties were of the greatest quality when the substrate bias voltage of -150 V was used. In addition, it was confirmed that the PV and Ra characteristics were improved by the deposition of the DLC thin film.

• 한국전기전자재료학회논문지
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• 제27권5호
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• pp.312-316
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• 2014

Photoemission is a process in which photons are converted into free electrons. Photocathodes are the typical materials for the process. They emit electrons when a light is irradiated upon. The traditional method of manufacturing photocathodes is complicated, requires specialized equipment, and is limited very small sized samples. $Cs_3Sb$ photocathode was formed on a substrate in $N_2$ atmospheric conditions. The photocathode formation was a gas phase reaction with the substrate. Vacuum devices were made to test electron emission characteristics of the formed photocathode. Visible light of wavelength 475 nm was used for the primary light source. The results showed high current density and long term stability of the photoelectron emission.

• 한국정밀공학회지
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• 제28권7호
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• pp.783-788
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• 2011

The recent development of bio-ceramic material is being studied in various bio-material engineering field. There are lots of technical difficulties because manufacturing or bonding technique are required bio-friendliness, cleanliness and persistence. Zirconia ceramic powder is cladded on Ti-6AI-4V metallurgically by laser cladding processing. Laser cladding system with powder feeding delivery is designed and manufactured for optimum processing condition. Increasing of manufacturing speed and good quality of clad layer are achieved by application of preheating of substrate before laser cladding. The thin dilution and good clad layer on the substrate are obtained for applications of bio-materials such as the dental materials and the articulated joints of human body.

• E2M - 전기 전자와 첨단 소재
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• 제9권5호
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• pp.470-475
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• 1996

Fiber-textured diamond films have been deposited on scratched silicon(100) substrate by micro wave .plasma enhanced chemical vapor deposition at the condition of micro wave power : 950 W, pressure : 60 torr, H$_{2}$ gas flow rate : 50 sccm, CH$_{4}$ gas flow rate : 1.5 sccm, substrate temperature : about 900.deg. C and deposition time : 20 hours. The films were characterized by mean of scanning electron microscopy, Raman spectroscopy and X-ray analysis.

• 한국전기전자재료학회논문지
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• 제13권6호
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• pp.459-466
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• 2000

For the applications in the ultra-large-scale-integration (ULSI) metallization processing copper thin films have been prepared by metal organic chemical vapor deposition (MOCVD) technology on TiN/Si substrates. The films have been deposited with varying the experimental conditions of substrate temperatures and copper source vapor pressures. The films were then annealed in a vacuum condition after the deposition and the annealing effect to the electrical conductivity of the films was measured. The grain size and the crystallinity of the films were observed to be increased by the post annealing and the electrical conductivity was also increased. The best electrical property of the copper film was obtained by in-situ annealing treatment at above 40$0^{\circ}C$ for the sample prepared at 18$0^{\circ}C$ of the substrate temperature.

• Journal of Welding and Joining
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• 제19권5호
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• pp.481-485
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• 2001

Laser cladding processing allows rapid transfer of heat to the material being processed with minimum conduction into base metal. The effect of $CO_2$ laser cladding with high viscosity mixed powders was investigated. High viscosity mixed powder consists of bronze powder and flux that is used at a high temperature condition. The mixed powder has a high viscosity that it can be easily pasted over a curved or slope substrate. The device for mixed powder was designed and manufactured. It consists of the high viscosity mixed powder feeding system, the preheating system and the shielding gas system which prevents the clad layer from being oxidized. The results of experiment indicated that the feed rate of high viscosity mixed powder was important for later cladding with mixed powder feeding. The high viscosity mixed powder and substrate must be preheated to prevent porosity from breaking at the clad layer. The experimental result shows that the high viscosity mixed can be applied for laser cladding process.