• 세라미스트
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• 제22권2호
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• pp.133-145
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• 2019

Thermoelectric energy conversion has attracted much attention because it can convert heat into electric power directly through solid state device and vice versa. Current research is aimed at increasing the thermoelectric figure of merit (ZT ) by improving the power factor and reducing the thermal conductivity. Although there have been significant progresses in increasing ZT of material systems composed of Bi, Te, Ge, Pb, and etc. over the last few decades, their relatively high cost, toxicity, and the scarcity have hindered further development of thermoelectrics to expand practical applications. In this paper, we review the current status of research in the fields of nanostructured thermoelectric materials with eco-friendly and low cost elements, such as skutterudites and oxides, for mid-high temperature applications, highlighting the strategies to improve thermoelectric performance.

• 수산해양교육연구
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• 제16권2호
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• pp.210-217
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• 2004

Cooling technology has been a vital prerequisite for the rapid, if not explosive, growth of the electronic equipment industry. This has been especially true during the last 20 years with the advent of intergrated circuit chips and their applications in computers and related electronic products. The purpose of this study is to develop a telecommunication equipment cooling system using a thermoelectric module combined with cooling fan. Thermoelectric module is a device that can perform cooling only by input of electric power. In the present study, the cooling package using the thermoeletric module has been developed to improve the thermal performance. The cooling characteristics of the electronic chip was placed into the subrack and it can be rapidly assembled or disassembled in the equipment rack. As a preliminary experiment, the cooling performances between a conventional way using a cooling fin and a proposed method applying the thermoelectric module was comosed and analyzyed. The cooling performance at a simulated electronic component packaging a thermomodule operated well.

• Carbon letters
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• 제21권
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• pp.8-15
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• 2017

The thermoelectric Seebeck and Peltier effects of a single walled carbon nanotube (SWCNT) quantum dot nanodevice are investigated, taking into consideration a certain value of applied tensile strain and induced ac-field with frequency in the terahertz (THz) range. This device is modeled as a SWCNT quantum dot connected to metallic leads. These two metallic leads operate as a source and a drain. In this three-terminal device, the conducting substance is the gate electrode. Another metallic gate is used to govern the electrostatics and the switching of the carbon nanotube channel. The substances at the carbon nanotube quantum dot/metal contact are controlled by the back gate. Results show that both the Seebeck and Peltier coefficients have random oscillation as a function of gate voltage in the Coulomb blockade regime for all types of SWCNT quantum dots. Also, the values of both the Seebeck and Peltier coefficients are enhanced, mainly due to the induced tensile strain. Results show that the three types of SWCNT quantum dot are good thermoelectric nanodevices for energy harvesting (Seebeck effect) and good coolers for nanoelectronic devices (Peltier effect).

• 한국정보통신학회:학술대회논문집
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• 한국정보통신학회 2012년도 추계학술대회
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• pp.255-258
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• 2012

본 논문에서는 온도 차에 의해 기전력이 발생하는 제베크효과를 이용한 열전소자로 전기에너지를 발생시키고, 전압이 최대전력이 발생하는 지점에서 동작하도록 하는 MPPT 제어기능을 갖는 에너지 하베스팅 회로를 설계하였다. 설계된 회로는 열전소자의 오픈 전압을 주기적으로 샘플링 한 후, MPPT 제어 회로를 통해 최대전력 발생 지점인 오픈전압의 1/2에 해당하는 전압을 유지하면서 열전소자로부터 수확된 에너지를 스위치를 통해 부하로 전달하는 역할을 한다. 제안된 열전에너지 하베스팅 회로는 $0.35{\mu}m$ CMOS 공정으로 설계하였고 설계한 회로의 칩 면적은 패드를 제외하고 $1168.7{\mu}m{\times}541.3{\mu}m$이다.

• 대한기계학회:학술대회논문집
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• 대한기계학회 2008년도 추계학술대회A
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• pp.1829-1832
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• 2008

This paper reports a novel gas sensing method by using a thermoelectric device, thermopile in this case, with an embedded tin oxide catalyst. By using a thin catalyst film, the response time and recovery time were remarkably improved. The fabricated gas sensor was characterized through detecting NOx gas with various concentrations.

• 마이크로전자및패키징학회지
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• 제11권3호
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• pp.83-89
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• 2004

NTC 써미스터를 내장시킨 소형의 열전 냉각 모듈을 제작하고 LD와 같은 광통신부품에 적용하기 위한 온도제어 및 항온유지 특성을 분석하였다 BiTe계 열전반도체 21쌍으로 구성된 열전 모듈은 크기 $7.2 mm{\times}9 mm{\times}2.2 mm$이고, 내장된 써미스터의 빠른 응답속도로 인해 정밀온도제어가 가능하다. 열전 모듈은 성능 지수(Z) $2.5{\times}10^{-3}$/K, 300 K에서 최대 온도차(${\Delta}T_{max}$) 72 K, 최대 흡열량($Q_{max}$) 2.2W 값을 나타내었으며 온도 제어 정밀도는 대기 중에서 ${\pm}0.1^{\circ}C$내였다. 이는 광통신 부품의 작동 환경 안정성을 확보할 수 있는 항온제어용 소형 열전 모듈로서 적용이 가능하다.

• 마이크로전자및패키징학회지
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• 제26권4호
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• pp.149-156
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• 2019

5쌍의 Bi₂Te₃계 p-n 가압소결체 열전레그들로 구성되어 있으며 상하부 기판이 없고 내부는 polydimethylsiloxane (PDMS)로 충진되어 있는 신축열전모듈을 형성하고, 이의 신축특성과 발전특성을 분석하였다. 신축열전모듈에 변형률 0~0.1 범위의 신축변형 싸이클을 10회 인가하여도 모듈의 integrity가 잘 유지되었으며, 인장변형률이 0.2로 증가시 Cu 전극과 열전레그 사이의 접합부 파단에 의해 모듈이 open 되었다. 신축열전모듈은 열전레그 양단간의 온도차가 2.2 K일 때 4.6 mV의 open circuit 전압을 나타내었으며, 변형률 0~0.1 범위의 인장변형에 의한 open circuit 전압의 변화는 5% 미만이었다. 신축열전모듈은 0.1의 변형률로 인장된 상태에서 레그 양단간 온도차 2.2 K에 의해 18.5 ㎼의 최대발전출력을 나타내었다.

• 융복합기술연구소 논문집
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• 제3권1호
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• pp.19-23
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• 2013

This study is concerned with air-conditioning system in use of thermoelectric device. It is introduced that the well designed structures for better cooling & heating performance with high efficiency. And also it is performed that the system performance test of four types trial products for the use of hybrid commercial vehicle. System performance is affected by many component parts, especially heat sink design & power control method. It is applied that dual extrusive fin tube with buffer zone for the effective radiating of circulating liquid in tube. And also it is applied that power supply method with constant-current system. It is attained that system cooling capacity is 1.2kW, COP is 0.95.

• 전자공학회논문지A
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• 제32A권3호
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• pp.124-133
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• 1995

A theoretical self-consistent thermoelectric model has been developed for optimal thermal design in the self-signal processing infraed detectors. The model is achived by employing the coupled thermoelectric equation which allows which allows the simultaneous investigation of the termal and electrical aspects of device behavior. The thermal limitation of detectivity and responsivity are determined by the enegy gap, carrier concentration, lifetime, and mobility as a function of the temperature. The calculated results indicate that the detectivity is decreased at bias fields above about 50 V/cm, because the performence is limiting by temperature when the bias voltage reached the level associated with Joule heating. It has been also found that the improvement in the mid-band modulation transfer function(MTF) may be restricted by increasing the bias fields. Further, the important paramerers in the thermal optimization of SPIR detector, such as temperature in the device, ambipolar velocity, element thickness and length, are also considered. The analytical study provides a mathematical basis for optimal design of such a photoconductive IR detector and the agreement between the experimental and theoretical results are seen to be good.

• 진공이야기
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• 제1권4호
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• pp.21-24
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• 2014

Thermolectric devices could convert temperature gradient into electricity (Seebeck effect) and electric power into temperature gradient across the themoelectric element (Peltier effect). $Bi_2Te_3$ has been widely used as thermoelectric material for more than 40 years, due to the superior thermoelctric characteristics. However, Bi and Te materials are predicted to face supply shortage, giving strong necessity for the development of new thermoelctric materials. Based on the theoretical prediction, nanostructure are expected to give dramatic enhnacement of thermoelectirc characteristics by controlling phonon propagation. Thus, silicon, which had been considered as improper material for thermoelectricity, is now being considered as strong cadidate material for thermoelectricity. This review will focus on the nanotechnology applied research activities in silicon as thermoelectric materials.