• 한국전기전자재료학회논문지
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• 제21권6호
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• pp.552-555
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• 2008

The purpose of this study was to find a best condition of fabricating lead zirconate thin film by sol-gel method, especially to find mol ratio and post annealing temperature. Lead zirconate thin film was made by spin coating method. The ratios of Pb and Zr of precursors were 1:0.8, 1:1.0, and 1:1.2. Annealing temperature of films were $600^{\circ}C$, $700^{\circ}C$, and $800^{\circ}C$ for 1 minute. Crystal structure was observed from XRD and antiferroelectricity was observed from hysteresis curves. The optimum mol ratio of Pb:Zr is 1:0.8 and annealing temperature is $800^{\circ}C$.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2009년도 제40회 하계학술대회
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• pp.1529_1530
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• 2009

The process conditions for fabricating p-type silicon pillars were optimized by controlling current density, bath temperature. To get best process flexibility for pillar arrays formation, three factors affecting pillar formation were changed. First, the solution bath was designed to keep constant temperature during the experiment irrespective of external temperature. Second, the counter Pt electrode was changed from rod type to mesh to obtain uniform distribution of current density. Third, Cr-Cu alloy electrode instead of Cu was used to increase electrode current density.

• Bulletin of the Korean Chemical Society
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• 제30권10호
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• pp.2245-2248
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• 2009

This paper demonstrates room temperature chemical vapor deposition (RTCVD) for fabricating titania inverse opals. The colloidal crystals of monodisperse polymer latex spheres were used as a sacrificial template. Titania was deposited into the interstices between the colloidal spheres by altermate exposures to water and titanium tetrachloride (Ti$Cl_4$) vapors. The deposition was achieved under atmospheric pressure and at room temperature. Titania inverse opals were obtained by burning out the colloidal template at high temperatures. The filling fraction of titania was controlled by the number of deposition of Ti$Cl_4$ vapor. The morphology of inverse opals of titania were investigated. The optical reflection spectra revealed a photonic band gap and was used to estimate the refractive index of titania.

• 한국세라믹학회지
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• 제37권4호
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• pp.302-307
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• 2000

The objective of this study was to investigate the sintering behavior, crystallization characteristic of glass-ceramic and optimal sintering condition on the glass/ceramic composite for fabricating substrate of LTCC. Glass/ceramic composite was made from alumina powder and glass frit, which was composed of SiO2-TiO2-RO-PbO/(R: Ba, Sr, Ca), and was sintered for 0, 30, 60minutes in the temperature range from 700$^{\circ}C$ to 1000$^{\circ}C$. Properties of frit and glass/ceramic compsoite were analyzed by DTA, XRD, SEM and Network Analyzer and so on. Main sintering mechanism was densification occurred above 730$^{\circ}C$ by viscous flow and crystallization starting about 780$^{\circ}C$ affected sintering also. So viscous flow was affected by sintering temperature, duration time, and creation of crystallization phase etc. From this study, it was possible to fabricate glass/ceramic composite by changing sintering temperature and duration time.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2005년도 추계학술대회 논문집
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• pp.272-274
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• 2005

A simple method for fabricating micro/nanoscale hierarchical structures is presented using a two-step temperature-directed capillary molding technique. This lithographic method involves a sequential application of molding process in which a uniform polymer-coated surface is molded with a patterned mold by means of capillary force above the glass transition temperature of the polymer. Using this approach, multiscale hierarchical structures for biomimetic functional surfaces can be fabricated with precise control over geometrical parameters and the wettability of a solid surface can be designed in a controllable manner.

• 한국전기전자재료학회논문지
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• 제26권2호
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• pp.144-150
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• 2013

A New Ag-pastes were developed for integrating the high efficiency mono-Si solar cell. The pastes were the mixture of 84 wt% Ag, 2 wt% glass frit, 11 wt% solvent of buthyl cabitol acetate, and 3 wt% additives. After fabricating the Ag-pastes by using a 3-roll mill, they were coated on a $SiN_x$/n+/p- stacks of a commercial mono-Si solar cell. And the post-thermal process was also optimized by varying the process conditions of peak temperature. The optimized solar cell efficiency on a 6-inch mono-Si wafer was 18.28%, which was the one of the world best performances. It meaned that the newly developed Ag-paste could be adopted to fabricate a commercial bulk Si solar cell.

• 한국정밀공학회지
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• 제32권9호
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• pp.773-779
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• 2015

The laser Powder Bed Fusion (PBF) system is currently recognized as a leading process. Due to the various materials employed such as thermoplastic, metal and ceramic composite powder, the application's use extends to machinery, automobiles, and medical devices. The PBF system's surface quality of prototypes and processing time are significantly affected by several parameters such as laser power, laser beam size, heat temperature and laminate thickness. In order to develop a more elaborate and rapid system, this study developed a new PBF system and sintering process. It contains a 3-axis dynamic focusing scanner system that maintains a uniform laser beam size throughout the system unlike the $f{\theta}$ lens. In this study, experiments were performed to evaluate the effects of various laser scanning parameters and fabricating parameters on the fusion process, in addition to fabricating various 3D objects using a PA-12 starting material.

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2023년도 봄 학술논문 발표대회
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• pp.125-126
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• 2023

Recently, heat island and dry island phenomena occur frequently due to land surface development and excessive energy consumption in urban areas. As a result, the surface temperature of the building and the entire temperature of its surroundings are increased, and as a result, the durability of the building is rapidly deteriorated. In order to suppress these causes, a method of maintaining the temperature of road heating wires was implemented as a temporary measure, but this did not predict climate change. Therefore, this study is a method to measure the compressive strength, density, and thermal conductivity of lightweight concrete using waste glass foam beads. After fabricating a simple chamber, the temperature and humidity of the inside and outside were measured with an Arduino device in consideration of external factors. Therefore, if waste glass foam beads made through proper mixing are constructed in the urban center, the quality of the urban can be improved.

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2023년도 가을학술발표대회논문집
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• pp.51-52
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• 2023

Recently, heat island and dry island phenomena occur frequently due to land surface development and excessive energy consumption in urban areas. As a result, the surface temperature of the building and the entire temperature of its surroundings are increased, and as a result, the durability of the building is rapidly deteriorated. In order to suppress these causes, a method of maintaining the temperature of road heating wires was implemented as a temporary measure, but this did not predict climate change. Therefore, this study is a method to measure the compressive strength, density, and thermal conductivity of light weight concrete using waste glass foam beads. After fabricating a simple chamber, the temperature and humidity of the inside and outside were measured with an Arduino device in consideration of external factors. Therefore, if waste glass foam beads made through proper mixing are constructed in the urban center, the quality of the urban can be improved.

• 한국복합재료학회:학술대회논문집
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• 한국복합재료학회 2002년도 춘계학술발표대회 논문집
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• pp.207-210
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• 2002

Metal matrix composites(MMCs) are increasingly attractive for high technology components such as aerospace applications and transportations due to their high strength, stiffness, and toughness. Many processes for fabricating MMCs have been developed, and relatively simple Foil-Fiber-Foil method is usually employed in solid state consolidation processes. During the consolidation processes at high temperature, densification occurs by the inelastic flow of the matrix materials, and the process is coupled with the conditions of pressure, temperature and volume fraction of fiber and matrix materials. This is particularly important in titanium matrix composites, and thus a generic model based on micro-mechanical approaches enabling the evolution of density over time to be predicted has been developed. The mode developed is then implemented into FEM so that practical process simulation has been carried out. Further the experimental investigation of the consolidation behavior of SiC/Ti-6Al-4V composites using vacuum hot pressing has been performed, and the results obtained are compared with the model predictions.