• Proceedings of the Korean Magnestics Society Conference
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• 2007.05a
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• pp.129.2-129.2
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• 2007

• Proceedings of the Korean Magnestics Society Conference
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• 2009.05a
• /
• pp.112-113
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• 2009

• Proceedings of the Korean Magnestics Society Conference
• /
• 2002.04a
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• pp.50-51
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• 2002

• Proceedings of the Korean Magnestics Society Conference
• /
• 2002.04a
• /
• pp.54-55
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• 2002

• Proceedings of the Korean Magnestics Society Conference
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• 2000.09a
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• pp.305-306
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• 2000

• Proceedings of the Materials Research Society of Korea Conference
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• 1994.05a
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• pp.46-47
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• 1994

• 한국초전도학회:학술대회논문집
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• v.15
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• pp.8-8
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• 2005

• Proceedings of the Materials Research Society of Korea Conference
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• 1998.11a
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• pp.63-63
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• 1998

No Abstract.see full/text

• Proceedings of the Materials Research Society of Korea Conference
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• 2010.05a
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• pp.11.2-11.2
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• 2010

Photovoltaic devices are promising candidates as affordable and large-area renewable energy sources, which can replace the fossil-fuel-based resources. Especially, thin film solar cells have attracted increasing research attention, since they have a great advantage of low production cost. From the physical point of view, the photovoltaic devices can provide us interesting questions, how to enhance the light absorption and the carrier collection efficiency. A lot of approaches would be possible to address these issues. We have focused on two major topics relevant to photovoltaic device physics; (1) light management using surface plasmons and (2) junction characterizations aiming at proper interface engineering. Regarding the first topic, we have investigated the influences of Ag under-layer morphology on optical properties of ZnO thin films. The experimental results suggested that coupling between the surface plasmon polaritons at the ZnO/Ag interface and excitons in ZnO should play important roles in reflectivity of the ZnO/Ag thin films, which are widely used back reflector structures in thin film solar cells. For the second topic, we have carried out scanning probe microscopy studies of Schottky junctions consisting of photovoltaic materials. Such a research is very helpful to understand the correlation between the defects (e.g., grain boundaries) and local electrical properties. We will introduce some of the recent experimental results and discuss the physical significance.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.59 no.11
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• pp.2038-2042
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• 2010

In this paper, we confirmed the thermal & optical properties for improving the heat transfer coefficient by changing the via hole size and in FR4 PCB with the same area. Osram 1W power LED Package (Golden Dragon) was used and the K-factor which is relative constant between LED junction temperature and forward bias was measured with power source meter(KEITHLEY 2430) to measure the thermal resistance from PCB configuration. As results, thermal resistance in metal PCB came out to the lowest as $26 [^{\circ}C/W]$ and thermal resistance in FR4 PCB without via-holes emerged as the highest as $69 [^{\circ}C/W]$. However thermal resistance of FR4 PCB could have decreased until $32[^{\circ}C/W]$ in 0.6 mm by using the via hole. Also, the luminous flux could have improved, too.