• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
• /
• 2002.08a
• /
• pp.58-63
• /
• 2002

For the experiment the four types of spacer were distinguished by arrangement. The flashover characteristic on each types of spacer was investigated and the flashover phenomena were observed to understand breakdown mechanism in liquid nitrogen($LN_{2}$). The spacer should be placed interior coil as an insulator, a cooling channel and s supporter of structures. The simulated electrode used in the experiment was made from five turns of HTS tape. Experimental results revealed that multi-layer and barrier effects did work well in Air but did not in $LN_{2}$. These result suggested that the flashover in LN2 caused by the bubbles due to partial discharge at micro gap, g. The flashover characteristics decreased to 70% when g is 0.2 mm. The degradation was improved by even treatment on surface of coil electrode.

• Proceedings of the Korean Vacuum Society Conference
• /
• 2013.08a
• /
• pp.139.2-139.2
• /
• 2013

6" Multi-crystal Silicon wafer has etched suing a remote - type RF Dielectric barrier discharge (RF DBD) at atmospheric pressure. DBD source is composed of Al electrode and coated Al2O3 dielectric as function of Ar/NF3 gas combination and input power used 13.56 MHz power supply. Ar gas flow rate is changed from 2 to 10 Slm, and NF3 flow rate is changed from 0.2~1 slm. At the result, NF3 flow rate Si etching rate also increase whit the increasing of NF3 flow rate But at 2 slm etching rate was decrease. In this experience, Max etching rate is 2.3 ${\mu}m/min$ when the scan time is 45 sec.

• Proceedings of the Korea Information Processing Society Conference
• /
• 2015.04a
• /
• pp.927-928
• /
• 2015

무안경 3D 입체 디스플레이 장치는 패럴렉스 배리어(parallax barrier)와 렌티률러 렌즈(Lenticular lens)의 기반의 장치로 구분된다. 무안경 업체 디스플레이 장치를 통하여 입체영상을 디스플레이하기 위해서는 다중 시점(multi-view) 촬영 영상들의 서브픽셀 인터레이싱 방법을 통하여 하나의 영상으로 합성되어야 한다. 본 연구는 렌티큘러 렌즈 기반의 입체 디스플레이 장치에서 렌티큘러 렌즈의 속성에 따라 적응적으로 서브픽셀 인터레이싱 될 수 있는 기법을 제안하기 위한 사전 연구로서 기존에 발표된 서브픽셀 인터레이싱 기법의 종류를 분류하고 각 기법의 특성을 분석하고자 한다.

• Journal of Sensor Science and Technology
• /
• v.33 no.3
• /
• pp.147-151
• /
• 2024

The importance of Wireless Sensor Networks is becoming more evident owing to their practical applications in various areas. However, the energy problem remains a critical barrier to the progress of WSNs. By reducing the energy consumed by the sensor nodes that constitute WSNs, the performance and lifespan of WSNs will be enhanced. In this study, we introduce an energy-efficient ternary modulator that employs multi-threshold CMOS for logic conversion. We optimized the design with a low-power ternary gate structure based on a pass transistor using the MTCMOS process. Our design uses 71.69% fewer transistors compared to the previous design. To demonstrate the improvements in our design, we conducted the HSPICE simulation using a CMOS 180 nm process with a 1.8V supply voltage. The simulation results show that the proposed ternary modulator is more energy-efficient than the previous modulator. Power-delay product, a benchmark for energy efficiency, is reduced by 97.19%. Furthermore, corner simulations demonstrate that our modulator is stable against PVT variations.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
• /
• 2009.11a
• /
• pp.26-26
• /
• 2009

Vertically aligned arrays of mm-long multi-walled carbon nanotubes (MWCNTs) on Si substrates have been synthesized by water-assisted thermal chemical vapor deposition (CVD). The growth of CNTs was investigated by changing the experimental parameters such as growth temperature, growth time, gas composition, annealing time, catalyst thickness, and Al underlayer thickness. The 0.5-nm-thick Fe served as catalyst, underneath which Al was coated as a catalyst support as well as a diffusion barrier on the Si substrate. We grew CNTs by adding a little amount of water vapor to enhance the activity and the lifetime of the catalyst. Al was very good at producing the nm-size catalyst particles by preventing "Ostwald ripening". The Al underlayer was varied over the range of 15~40 nm in thickness. The optimum conditions for the synthesis parameters were as follows: pressure of 95 torr, growth temperature of $815^{\circ}C$, growth for 30 min, 60 sccm Ar + 60 sccm $H_2$ + 20 sccm $C_2H_2$. The water vapor also had a great effect on the growth of CNTs. CNTs grew 5.03 mm long for 30 min with the water vapor added while CNTs were 1.73 mm long without water vapor at the same condition. As-grown CNTs were characterized by using scanning electron microscopy (SEM), high resolution transmission electron microscopy (HRTEM), and Raman spectroscopy. High-resolution transmission electron microscopy showed that the as-grown CNTs were of ~3 graphitic walls and ~6.6 nm in diameter.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
• /
• 2008.11a
• /
• pp.259-259
• /
• 2008

The LTCC (Low Temperature Co-fired Ceramic) technology meets the requirements for high quality microelectronic devices and microsystems application due to a very good electrical and mechanical properties, high reliability and stability as well as possibility of making integrated three dimensional microstructures. The wet process, which has been applied to the etching of the metallic thin film on the ceramic substrate, has multi process steps such as lithography and development and uses very toxic chemicals arising the environmental problems. The other side, Plasma technology like ion beam sputtering is clean process including surface cleaning and treatment, sputtering and etching of semiconductor devices, and environmental cleanup. In this study, metallic multilayer pattern was fabricated by the ion beam etching of Ti/Pd/Cu without the lithography. In the experiment, Alumina and LTCC were used as the substrate and Ti/Pd/Cu metallic multilayer was deposited by the DC-magnetron sputtering system. After the formation of Cu/Ni/Au multilayer pattern made by the photolithography and electroplating process, the Ti/Pd/Cu multilayer was dry-etched by using the low energy-high current ion-beam etching process. Because the electroplated Au layer was the masking barrier of the etching of Ti/Pd/Cu multilayer, the additional lithography was not necessary for the etching process. Xenon ion beam which having the high sputtering yield was irradiated and was used with various ion energy and current. The metallic pattern after the etching was optically examined and analyzed. The rate and phenomenon of the etching on each metallic layer were investigated with the diverse process condition such as ion-beam acceleration energy, current density, and etching time.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
• /
• v.25 no.1
• /
• pp.44-47
• /
• 2012

The $TiO_2/Si_3N_4/Ag/Si_3N_4/TiO_2$ multi layered structure was designed for the possible application of transparent electrodes in PDP (Plasma Display Panel). Multi layered film was deposited on a glass substrate at room temperature by DC/RF magnetron sputtering system and EMP (Essential Macleod Program) was adopted to optimize the optical characteristics of film. During the deposition process, the Ag layer in $TiO_2/Ag/TiO_2$ became heavily oxidized and the filter characteristic was degraded easily. In thus study, Si3N4 layer was used as a diffusion buffer layer between $TiO_2$ and Ag. in order to prevent the oxidation of Ag layer in $TiO_2/Si_3N_4/Ag/Si_3N_4/TiO_2$ structure. It was confirmed that $Si_3N_4$ layer is one of candidate materials acting as diffusin barrier between $TiO_2/Ag/TiO_2$.

• Journal of Korean Society of Rural Planning
• /
• v.19 no.4
• /
• pp.307-317
• /
• 2013

The value and functionality of boundary barriers in rural villages have been neglected in the aspects as the buffer zone(boundary barrier) that links between the inside space(housing site) and the outside space(road). On this understanding, this study evaluated conservation value, economical efficiency and durability by the types and materials of the boundary barriers in rural village through Multi-attribute Decision Making. By applying to the current situations of boundary barriers on total 21 case study villages, each factor value was measured. And using Matrix Analysis Technique, the boundary barriers are classified into 4 types and the improvement ways for each type were proposed. As a result, the durability of boundary barriers in rural villages showed similarity value(more than 0.85 out of 1). But economical efficiency of those was low(less than 0.5 out of 1) and those functionalities were very lacking(about 0.3 out of 1). In the conclusion, the maintenance of boundary barriers in rural villages requires the policy that is able to complement conservation value and economical efficiency and is proper to the characteristic of each village. These renewable policies would contribute to the increase of the value of rural amenity as well as creation of economical and social value.

• Journal of Korean Society on Water Environment
• /
• v.20 no.5
• /
• pp.512-519
• /
• 2004

Hybrid barriers using reduction and immobilization were tested to remediate the groundwater contaminated with multi-pollutants in this study. Iron filings and HDTMA(hexadecyltrimethylammonium)-bentonite were simulated in columns to assess the performance of hybrid barriers for remediation of trichloroethylene(TCE)-contaminated water. TCE reduction rate for the mixture of iron filings and HDTMA-bentonite was about 7 times higher than that for iron filings, only suggesting the reduction of TCE was accelerated when HDTMA-bentonite was mixed with iron filings. TCE reduction rate for the two layers of iron and HDTMA-bentonite was nearly similar to that for iron filings alone, but the partition coefficient($K_d$) for the two layers was 4.5 times higher than for that iron filings only. TCE was immobilized in the first layer with HDTMA-bentonite, and then dechlorinated in the second layer with iron filings. HDTMA-bentonite may contribute to the increase in TCE concentration on iron surface so that more TCE can be reduced. Also, TCE removal in the hybrid barriers was not affected by chromate and naphthalene while the reduction rate of TCE with the co-existing contaminants by iron filings was significantly decreased. Significant TCE removal in this research indicates that the proposed hybrid barrier system has the potential to become the effective remediation alternative during the occurrence of oil shock. Also, if subsurface environments are contaminated with multi-pollutants that contain non-reducible compounds as well as reducible compounds such as TCE, the conventional reactive barriers cannot be applied to this subsurface environment, while the proposed hybrid system can be applied successfully.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
• /
• 2006.06a
• /
• pp.261-262
• /
• 2006

High temperature superconducting coated conductor has multi-layer structure of protecting layer/superconducting layer/buffer layer/metallic substrate. The buffer layer consists of multi layer, and the architecture most widely used in RABiTS approach is $CeO_2$(cap layer)/YSZ(diffusion barrier layer)/$CeO_2$(seed layer). Multi-buffer layer deposition required many times and process. Therefore single buffer layer deposition study reduce 2G HTS manufacture efforts. Evaporation technique for single buffer deposition method is used for the $CeO_2$ layer. $CeO_2$ single buffer film could be achieved in the chamber. Detailed deposition conditions (temperature and partial gas pressure of deposition) were investigated for the rapid growth of high quality $CeO_2$ single buffer film.