• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2003년도 하계학술대회 논문집 Vol.4 No.2
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• pp.868-871
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• 2003

In recent years, silicon carbide has emerged as an important material for MEMS application. In order to fabricate an SiC film based MEMS structure by using chemical etching method, high operating temperature is required due to high chemical stability. Therefore, dry etching using plasma is the best solution. SiC film was deposited by thermal CVD at the temperature of $1000^{\circ}C$ and pressure of 10 torr. SiC was dry etched with a reactive ion etching (RIE) system, using $SF_6/O_2$ and $CF_4/O_2$ gas mixture. Etch rate have been investigated as a function of oxygen concentration in the gas mixture, RF power, and working pressure. Etch rate was measured by surface profiler and FE-SEM. $SF_6/O_2$ gas mixture has been shown high etch rate than $CF_4/O_2$ gas mixture. Maximum etch rate appeared at 450W of RF power. $O_2$ dilute mixtures resulted in an increasing of etch rate up to 40%, and the superior anisotropic cross section was observed.

• 대한화학회지
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• 제62권2호
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• pp.93-98
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• 2018

Bis-GMA, TEGDMA, and camphorquinone were used as the main material, cross-linking agent, and photoinitiator, respectively. In addition, 2-isocyanatoethyl methacrylate was used as an additive for high strength, while the 3-hydroxypyridine was used as an additive for antibacterial activity. Photopolymerization was also carried out at a 440-480 nm wavelength and at about $1000mW/cm^2$ intensity for about 40 seconds. The breaking strength measurement of the samples showed that the breaking strength increased along with increasing the addition ratio of IEM, while it took less time until the polymerization was complete, thereby suggesting that the degree of polymerization has the tendency to increase. And also, compared to the size of the clear zone formed by ampicillin, the 3-hydroxypyridine group exhibited antimicrobial activity induced by ampicillin. The results of this study suggest that the use of 2-isocyanatoethyl methacrylate as an additive for high strength and 3-hydroxypyridine as an additive for improved antibacterial activity would improve the usability of the fabricated polymer as a dental resin cement material with high functionality.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2006년도 추계학술대회 논문집 전기물성,응용부문
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• pp.32-33
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• 2006

As next generation nonvolatile memory, chalcogenide-based phase change memory can substitute for a conventional flash memory from its high performance. Also, fast writing speed, low writing voltage, high sensing margin, low power consumption and repetition reliability over $10^{15}$ cycle shows its possibility. At our laboratory, we invented ${Ge_1}{Se_1}{Te_2}$ material to alternate with conventional ${Ge_2}{Sb_2}{Te_5}$ for improve its ability. We respect the ${Ge_1}{Se_1}{Te_2}$ material can be a solution for high power consumption problem and long time at 'set' performance. A conductivity experiment from variable temperature was performed to see reliability of repetition at read and write performance. Compare with conventional ${Ge_2}{Sb_2}{Te_5}$ material, these two materials are used as complex compound to get the finest parameter.

• 설비공학논문집
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• 제20권11호
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• pp.746-751
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• 2008

The best plan to reduce the building energy consumption is that the insulation performance should be improved because the insulation and airtight of building envelopes have an effect on the energy consumption basically. New insulation materials, which have the high performance and are above insulation standard, have been developed steadily. Because there are not studies on the building energy rating system and economic evaluation considering new insulation materials, these matters should be studied. In result alternatives, which applied 6 high performance material each, reduce the annual heating energy and raise the building energy rating. Applying the vacuum insulation material(Case 1, 2) and vacuum or triple glazing can retrieves the investment with $120 and $140$\sim$150 per barrel each.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2009년도 하계학술대회 논문집
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• pp.378-379
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• 2009

High intensity metal halide discharge lamp performance, specifically the generated luminous flux and light color content, depends critically on the arc tube design. Factors influencing the design and consequent lamp efficacy include : lamp size, geometry, arc tube composition, fill chemistry, electrode design and excitation modes. Shaping of Polycrystalline Alumina(PCA) can be realized by conventional ceramic processes. Several processes are applied nowadays. Well-known in the ceramic high pressure field for decades are the pressing and the extrusion method. Newly developed slurry and precious forming technologies give the one-body seamless tubes, which improve thickness uniformity and lighting performance. Now, we reported some optical properties with different arc tube structures of ceramic metal halide lamps.

• 한국전기전자재료학회논문지
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• 제25권3호
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• pp.187-192
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• 2012

Development of new efficient, high voltage switching devices with wide safe operating area and low on-state losses has received considerable attention in recent years. One of those structures with a very effective geometrical design is the trench gate Insulated Gate Bipolar Transistor(IGBT).power IGBT devices are optimized for high-voltage low-power design, decided to aim. Class 1,200 V NPT Planer IGBT, 1,200 V NPT Trench IGBT for class has been studied.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2010년도 하계학술대회 논문집
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• pp.128-128
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• 2010

The high-voltage X-ray generator recently used is very popular, because that can be miniaturized, increased in generating efficiency, elaborated in output control. All these features are available with high-frequency made by using an inverter, the fast switching semiconductor device. In this paper to identify the differences among types of rectification, we compared output ripple with full-wave rectification and dual-voltage rectification methods.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2010년도 하계학술대회 논문집
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• pp.352-352
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• 2010

Silicon Carbide (SiC) power device possesses attractive features, such as high breakdown voltage, high-speed switching capability, and high temperature operation. In general, device design has a significant effect on the switching characteristics. In this paper, we report the effect of the P-base doping concentration ($N_{PBASE}$) on the transient characteristics of 4H-SiC DMOSFETs. By reducing $N_{PBASE}$, switching time also decreases, primarily due to the lowered channel resistance. It is found that improvement of switching speed in 4H-SiC DMOSFETs is essential to reduce the and channel resistance. Therefore, accurate modeling of the operating conditions are essential for the optimization of superior switching performance.

• 한국분말야금학회:학술대회논문집
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• 한국분말야금학회 2006년도 Extended Abstracts of 2006 POWDER METALLURGY World Congress Part 1
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• pp.385-386
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• 2006

For attaining optimum fatigue resistance of PM steels, high density levels are necessary. In this work, sintered steels Fe-1.5%Mo-0.6%C and Fe-1.5%Cr-0.2%Mo-0.6%C were produced with density levels of 7.1 to $7.6\;g.cm^{-3}$. Ultrasonic fatigue testing with 20 kHz was performed in push-pull mode up to 10E9 cycles. It was shown that the fatigue endurance strength is strongly improved by higher density levels, but also higher sintering temperatures are beneficial. The Cr-Mo steels proved to be superior to the plain Mo alloyed, due to a more favourable as-sintered matrix microstructure.

• 한국전기전자재료학회논문지
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• 제26권3호
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• pp.190-193
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• 2013

Power MOSFET and Power IGBT is develop in power savings, high efficiency, small size, high reliability, fast switching, low noise. Power MOSFET can be used high-speed switching transistors devices. Power MOSFET is devices the voltage-driven approach switching devices are design to handle on large power, power supplies, converters. In this paper, design the 80V MOSFET Planar Gate type, and design the Trench Gate type for realization of low on-resistance. For both structures, by comparing and analyzing the results of the simulation and characterization.