• Transactions on Electrical and Electronic Materials
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• 제13권6호
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• pp.292-296
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• 2012

An optimum heat sink for a 30 W chip on board (COB) LED down-light is designed, fabricated, and characterized. By using the SolidWorks Flow simulator and thermal analysis software, the thermal characteristics of the optimum heat sink is analyzed. Four different types of heat sink are simulated and an optimum structure of the heat sink is found. The simulated temperature of the heat sink when operating the LED down-light is $55.9^{\circ}C$, which is only a difference of $2^{\circ}C$ from the measured temperature. In order to reduce the temperature further, a copper spreader is introduced to the heat sink. The temperature of the heat sink with the copper spreader is $3^{\circ}C$ lower than without the copper spreader.

• 대한기계학회:학술대회논문집
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• 대한기계학회 2001년도 춘계학술대회논문집D
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• pp.612-617
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• 2001

This paper reports the cooling performance of a PDP(plasma display panel) with a heat spreader by means of numerical analysis. Due to the simplifications and assumptions inherent in the analysis, computed results are found to differ those of the experiment by 13%. Calculation shows a maximum temperature of $65^{\circ}C$ for the plasma glass, as opposed to the allowable temperature of $90^{\circ}C$, producing a temperature difference of $25^{\circ}C$ between the upper and lower regions. This is enough to cause cracks in the plasma glass. In order to avoid this, more ventholes are added at the upper center region of the back cover, thereby causing a $3^{\circ}C$ drop in the maximum temperature, which reduces the temperature difference to $12^{\circ}C$. The new design gives more uniform temperature distribution across the plasma glass.

• 대한기계학회:학술대회논문집
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• 대한기계학회 2005년도 창립60주년 기념 추계 학술대회
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• pp.16.1-16.1
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• 2005

• Journal of Mechanical Science and Technology
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• 제18권4호
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• pp.681-688
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• 2004

For use of the thermal cycle of the biochemical fluid sample, the isothermal temperature source with a large surface area was designed, fabricated and its thermal characterization was experimentally evaluated. The comprehensive overview of the technology trend on the temperature control devices was detailed. The large surface area isothermal temperature source was realized by using the vapor chamber heat spreader. The cost-effectiveness and simple manufacturing process were achieved by using the metal-etched wick structure. The temperature distribution was quantitatively investigated by using IR temperature imaging system at equivalent temperatures to the PCR thermal cycle. The standard deviation was measured to be within 0.7$^{\circ}C$ for each temperature cycle. This concludes that the presented isothermal temperature source enables no temperature gradient inside bio-sample fluid. Furthermore it can be applied to the cooling of the electronic devices due to its slimness and low thermal spreading resistance.

• 한국소성가공학회:학술대회논문집
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• 한국소성가공학회 2007년도 춘계학술대회 논문집
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• pp.60-65
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• 2007

According to the customers' demands, cellular phones are getting thinner and thinner in spite that their functions are getting more complex and flexible. Based on this trend, we are willing to propose new design of ultra slim cellular phone with multi-hinges which can provide thinner feature and wider active area than the current merchandised one. To make it come true, smaller and stronger mechanical parts would be necessary and more researches would be carried out in the near future. Moreover, the new frame of ultra slim cellular phone has the problem in heat propagation due to its thin feature and multi function. In this paper, slim heat-spreader would be proposed as a candidate to resolve the problem of heat transfer in the new cellular phone. To investigate the applicability of heat-spreader to cellular phones, prototypes were fabricated and verified.

• 대한기계학회:학술대회논문집
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• 대한기계학회 2005년도 창립60주년 기념 추계 학술대회
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• pp.41.1-41.1
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• 2005

• 대한기계학회:학술대회논문집
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• 대한기계학회 2005년도 창립60주년 기념 추계 학술대회
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• pp.41.2-41.2
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• 2005

• 대한기계학회논문집B
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• 제35권6호
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• pp.551-560
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• 2011

본 연구에서는 열분산기 및 자연대류 히트 싱크로 구성된 집광형 태양전지 모듈용 냉각 장치를 제안하고자 한다. 이를 위해, 기존 연구자들의 해석적 연구를 바탕으로 집광형 태양전지 모듈용 열분산기 및 자연대류 히트 싱크를 설계하였다. 제안된 냉각 장치의 성능을 평가하기 위하여, 발열량과 수직 기준 경사각 변화에 따른 열성능 평가실험을 수행하였다. 실험결과로부터, 제안된 냉각 장치가 집광형 태양전지 모듈의 설계 조건을 만족하는 것을 확인하였다. 마지막으로 발열량과 수직기준 경사각 변화에 따른 자연대류 히트 싱크의 열성능을 예측할 수 있는 상관식을 제시하였다.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2010년도 추계학술대회 논문집
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• pp.593-594
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• 2010

• 센서학회지
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• 제23권4호
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• pp.234-237
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• 2014

In this paper, a copper foil-thick grapheme (thin graphite sheet)-copper foil structure is reported to achieve mechanically strong and high thermal conductive layer suitable for heat spreading components. Since graphene provides much higher thermal conductivity than copper, thick graphene embedded copper layer can achieve higher effective thermal conductivity which is proportional to graphene/copper thickness ratio. Since copper is nonreactive with carbon material which is graphene, chromium is used as adhesion layer to achieve copper-thick graphene-copper bonding for graphene embedded copper layer. Both sides of thick graphene were coated with chromium as an adhesion layer followed by copper by sputtering. The copper foil was bonded to sputtered copper layer on thick graphene. Angstrom's method was used to measure the thermal conductivity of fabricated copper-thick graphene-copper structure. The thermal conductivity of the copper-thick graphene-copper structures is measured as $686W/m{\cdot}K$ which is 1.6 times higher than thermal conductivity of pure copper.