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Lee, Se-Il;Lee, Seung-Min;Park, Dae-Hee
- Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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- v.24 no.12
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- pp.57-63
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- 2010
The efficiency of LED package is increasing by applying the high power, and a existing lighting is changing as the LED lighting. However, many problems have appeared by heat. Therefore, in order to solve thermal problems, LED lighting is designing in several ways, but the advantages of LED lighting is fading due to increase the prices and volumes. In this study, we try to improve the thermal performance by formation of via holes. The junction temperature and thermal resistance in the FR4-PCB with via-holes of 0.6[mm] was excellent in experiment and FR4-PCB with Via-holes of 0.6[mm] was excellent in simulation without solder. Further, the thermal resistance and the optical properties can be improved through a formation of via-holes.
https://doi.org/10.5207/JIEIE.2010.24.12.057 인용 PDF KSCI

Park, B.G.;Yang, H.D.;Choi, C.J.;Kim, J.Y.;Shim, K.H.
- Journal of the Korean Institute of Electrical and Electronic Material Engineers
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- v.22 no.11
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- pp.905-909
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- 2009
The new Junction Field Effect Transistors (JFETs) with Silicon-germanium (SiGe) layers is investigated. This structure uses SiGe layer to prevent out diffusion of boron in the channel region. In this paper, we report electrical properties of SiGe JFET measured under various design parameters influencing the performance of the device. Simulation results show that out diffusion of boron is reduced by the insertion SiGe layers. Because the SiGe layer acts as a barrier to prevent the spread of boron. This proposed JFET, regardless of changes in fabrication processes, accurate and stable cutoff voltage can be controlled. It is easy to maintain certain electrical characteristics to improve the yield of JFET devices.
https://doi.org/10.4313/JKEM.2009.22.11.905 인용 PDF KSCI

Park, Jin-Seok
- Proceedings of the KIEE Conference
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- 1997.11a
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- pp.683-687
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- 1997
The purpose of this work is to develop a highly reliable solar cell based on the diamond-like carbon(DLC)/silicon heterojunction. Thin films of DLC have been deposited by employing both filtered cathodic vacuum arc(FCVA) and magnetron plasma-enhanced chemical vapor deposition(m-PECVD) systems. Structural, electrical, and optical properties of DLC films deposited are systematically analyzed as a function of deposition conditions, such as magnetic field, substrate bias voltage, gas pressure, and nitrogen content. The I-V measurement has been used to elucidate the mechanism responsible for the conduction process in the DLC/Si junction. Photoresponse characteristics of the junction are measured and its reliability against temperature and light stresses is also analyzed.
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