• International Journal of Computer Science & Network Security
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• v.21 no.6
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• pp.252-257
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• 2021

The application of the principle of trigeneration allows to simultaneously provide electricity to power electronic devices, as well as heat and cold to create the necessary microclimate of the premises and increase efficiency compared to separate cooling and heating systems. The use of Peltier thermoelectric modules (TEM) as part of trigenerative systems allows for smooth and precise control of the temperature regime, high manufacturability and reliability due to the absence of moving parts, resistance to shock and vibration, and small weight and size parameters of the system. One of the promising areas of improvement of trigenerative systems is their modeling and optimization based on the automatic control theory. A block diagram and functional model of an energy-saving trigenerative climate control system based on Peltier modules are developed, and the transfer functions of an open and closed system are obtained. The simulation of the transient characteristics of the system with varying parameters of the components is performed. The directions for improving the quality of transients in the climate control system are determined, as well as the prospects of the proposed methodology for modeling and analyzing control systems operating in substantially nonlinear modes.

• Journal of the Microelectronics and Packaging Society
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• v.17 no.4
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• pp.89-94
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• 2010

Bi-Te films were processed by coevaporation of Bi and Te dual sources with variations of the mole ratio of the Bi and Te evaporation sources, and thermoelectric properties of the coevaporated Bi-Te films were characterized. The coevaporated Bi-Te films were n-type semiconductors and exhibited Seebeck coefficients of $-60{\sim}-80{\mu}V/K$. The Terich Bi-Te film, processed with Bi and Te dual sources of 30 mol% Bi : 70 mol% Te ratio, exhibited a power factor of $5{\times}10^{-4}W/m-K^2$. On the other hand, a power factor of $17.7{\times}10^{-4}W/m-K^2$ was obtained for the Bi-rich film coevaporated using Bi and Te dual sources of 90 mol% Bi : 10 mol% Te ratio.

• Korean Journal of Materials Research
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• v.20 no.6
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• pp.326-330
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• 2010

$CoSb_3$ Skutterudites materials have high potential for thermoelectric application at mid-temperature range because of their superior thermoelectric properties via control of charge carrier density and substitution of foreign atoms. Improvement of thermoelectric properties is expected for the ternary solid solution developed by substitution of foreign atoms having different valances into the $CoSb_3$ matrix. In this study, ternary solid solutions with a stoichiometry of $Co_{1-x}Ni_xSb_3$ x = 0.01, 0.05, 0.1, 0.2, $CoSb_{3-y}Te_y$, y = 0.1, 0.2, 0.3 were prepared by the Spark Plasma Sintering (SPS) system. Before the SPS synthesis, the ingots were synthesized by vacuum induction melting and followed by annealing. For phase analysis X-ray powder diffraction patterns were checked. All the samples were confirmed as single phase; however, with samples that were more doped than the solubility limit some secondary phases were detected. All the samples doped with Ni and Te atoms showed a negative Seebeck coefficient and their electrical conductivities increased with the doping amount up to the solubility limit. For the samples prepared by SPS the maximum value for dimensionless figure of merit reached 0.26, 0.42 for $Co_{0.9}Ni_{0.1}Sb_3$, $CoSb_{2.8}Te_{0.2}$ at 690 K, respectively. These results show that the SPS method is effective in this system and Ni/Te dopants are also effective for increasing thermoelectric properties of this system.

• Journal of the Microelectronics and Packaging Society
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• v.15 no.3
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• pp.1-8
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• 2008

Effects of annealing process in a reduction ambient on thermoelectric properties of the $(Bi,Sb)_{2}Te_3$ thin films prepared by thermal evaporation have been investigated. With annealing at $300^{\circ}C$ for 2 hrs in a reduction ambient(50% $H_2$+50% Ar), the crystallinity of the $(Bi,Sb)_{2}Te_3$ thin films were substantially improved with remarkable increase in the grain size. Seebeck coefficients of the $(Bi,Sb)_{2}Te_3$ thin films increased from$\sim90{\mu}V/K$ to $\sim180{\mu}V/K$ with annealing in the reduction ambient due to decrease in the hole concentration. Power factors of the $(Bi,Sb)_{2}Te_3$ thin films were remarkably improved for $5\sim16$ times with annealing in the reduction atmosphere. After annealing in the reduction ambient, a $(Bi,Sb)_{2}Te_3$ evaporated film exhibited a maximum power factor of $18.6\times10^{-4}W/K^{2}-m$.

• Journal of the Microelectronics and Packaging Society
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• v.11 no.3 s.32
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• pp.83-89
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• 2004

NTC thermistor embedded miniature thermoelectric module was fabricated for the precise temperature control of optical communication device such as laser diode (LD). The miniature thermoelectric module ($7.2 mm{\times}9 mm{\times}2.2 mm$) consists of 21 BiTe thermoelectric couples, the operating temperature is precisely controlled by embedded thermistor with quick response. The figure-of-merit (Z), maximum temperature difference (${\Delta}T_{max}$), maximum cooling capacity ($Q_{max}$) of the miniature thermoelectric module were $2.5{\times}10^{-3}$/K, 72 K, 2.2 W respectively and temperature could be controlled in range of ${\pm}0.1^{\circ}C$ accuracy in air. The fabricated miniature thermoelectric module is suitable for applications of the optical communication packaging.

• Journal of the Microelectronics and Packaging Society
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• v.7 no.4
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• pp.1-5
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• 2000

Properties of AC applied hot pressed ($Pb_{1-x}Sn_{x}$) Te thermoelectrics were investigated. Mechanical alloying process used to produce alloyed powder to reduce the inhomogeneity and to avoid vaporization of constituents. It showed an increase in the mechanical alloying time with increasing of Sn contents in ($Pb_{1-x}Sn_{x}$)Te. ($Pb_{1-x}Sn_{x}$)Te were sintered at 873 to 923K for 1-4 minutes, under 150 kgf/$\textrm{cm}^2$ by AC applied hot pressng method. The short sintering time of AC applied hot pressing process could reduce the vaporization of Te. The density of ($Pb_{1-x}Sn_{x}$) Te was more dependent on the sintering temperature than the sintering time. The p-n transition was observed at x=0.1 but only p type conduction behavior was observed at more than 20 mol% of Sn compositions. The maximum value of Seebeck coefficient is 250 $\mu$V/K for x=0.2 at 500K. As the amount of Sn increases, the peak value of Seebeck coefficient drops and shifts to higher temperature and the peak value of electrical conductivity decreased with increasing temperature.

• Journal of the Microelectronics and Packaging Society
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• v.25 no.3
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• pp.67-74
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• 2018

Thermoelectric thin film devices of the in-plane configuration consisting of 8 pairs of n-type $Bi_2Te_3$ and p-type $Sb_2Te_3$ legs were processed on Si submounts by electrodeposition. The thermoelectric generation characteristics of the thin film devices were investigated with respect to the apparent temperature difference ${\Delta}T$ caused by LED lighting as well as the change of the leg thickness. When ${\Delta}T$ was 7.4 K, the open circuit voltages of 6.1 mV, 7.4 mV, and 11.8 mV and the maximum output powers of 6.6 nW, 12.8 nW, and 41.9 nW were measured for the devices with the thermoelectric legs of which thickness were $2.5{\mu}m$, $5{\mu}m$, and $10{\mu}m$, respectively.

• Journal of the Microelectronics and Packaging Society
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• v.15 no.4
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• pp.41-49
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• 2008

Thermoelectric properties of the n-type Bi-Te and the p-type Bi-Sb-Te films were measured and the growth behaviors of the electrodeposited Bi-Te and Bi-Sb-Te nanowires were characterized. Filling ratios of 81% and 77% were obtained for electrodeposition of the Bi-Te and the Bi-Sb-Te nanowires, respectively, into the nano pores of 200 nm-diameter of an alumina template. A thermoelectric module, composed of the Bi-Te nanowires and the Bi-Sb-Te nanowires was processed by electrodeposition, and a resistance value of $15{\Omega}$ was measured between the Ni electrodes formed on the Bi-Te nanowires and the Bi-Sb-Te nanowires of the module.

• Journal of the Microelectronics and Packaging Society
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• v.15 no.4
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• pp.93-100
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• 2008

The one and two pair of oxide modules for high temperature thermoelectric power generation were fabricated with $Ca_{2.7}Bi_{0.3}Co_4O_9$(p-type) and $Ca_{0.96}Bi_{0.04}Mn_{0.96}Nb_{0.04}O_3$(n-type) on $Al_2O_3$ substrate. For the optimizing of the design process, contact resistance was derived from the results of the one pair modules, and then the resistance of two pair modules were calculated to use the derived data. Those values were compared with the measured values for the optimizing of this design process. The resistance of calculated and measured two pairs modules was 0.956 $\Omega$ and 1.110 Q $\Omega$ $T_h$=833 K, respectively, the difference of resistance was about 0.15 $\Omega$. From the result, proposed design process is effective for high temperature thermoelectric oxide modules fabrication.

• Composites Research
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• v.28 no.2
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• pp.70-74
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• 2015

In this paper, carbon nanotubes (CNTs) and micro glass bubbles (GBs) have been incorporated into a polyamide6 (PA6) matrix to impart thermoelectric properties. The spaces created in the matrix by GBs allows the formation of "segregated" CNT network. The tightly bound CNT network, if controlled properly, can serve as a conductive path for electron transport, while prohibiting phonon transport, which would provide an ideal configuration for thermoelectric applications. The CNTs and GBs were dispersed in a nylon-formic acid solution using horn sonication followed by coagulation in deionized water, and nanocomposite panels were fabricated using a hot press. The performance of nanocomposite panels was evaluated from thermal and electrical conductivities and Seebeck coefficient, and a thermoelectric figure of merit as high as 0.016 was achieved.