• Title/Summary/Keyword: figure-of-merit

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Control of Deposition Parameters in ITO Films: Figure of Merit

  • Kim, H.H.;Park, C.H.;Cho, M.J.;Lim, K.J.;Shin, J.H.;Park, K.J.
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 2001.11b
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    • pp.398-401
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    • 2001
  • Indium tin oxide films were deposited on unheated PET substrates by DC reactive magnetron sputtering of In-Sn (90-10 wt%) metallic alloy target. Electrical and optical properties of as-deposited films were systematically studied by control of the deposition parameters such as working pressure, DC power, and oxygen partial pressure. The figures of merit are important factors that summarize briefly the relationship between electrical and optical properties of transparent conducting films. The formulae of $T/R_{sh}$ and $T^{10}/R_{sh}$ are expressed as a function of transmittance and sheet resistance. The best values of those figures of merit were approximately 38.6 and $8.95({\times}10^{-3}\Omega^{-1})$ respectively.

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Control of Deposition Parameters in ITO Films: Figure of Merit

  • Kim, H.H.;Park, C.H.;M.J. Cho;K.J. Lim;J.H. Shin;Park, K.J.
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 2001.11a
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    • pp.398-401
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    • 2001
  • Indium tin oxide films were deposited on unheated PET substrates by DC reactive magnetron sputtering of In-Sn (90-10 wt%) metallic alloy target. Electrical and optical properties of as-deposited films were systematically studied by control of the deposition parameters such as working pressure, DC power, and oxygen partial pressure. The figures of merit are important factors that summarize briefly the relationship between electrical and optical properties of transparent conducting films. The formulae of T/R$\sub$sh/ and T$\^$10//R$\sub$sh/ are expressed as a function of transmittance and sheet resistance. The best values of those figures of merit were approximately 38.6 and 8.95 (x10$\^$-3/Ω$\^$-1/), respectively.

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Thermoelectric Properties of the n-type Bi2(Te0.9Se0.1)3 Processed by Hot Pressing with Dispersion of 0.5 vol% TiO2 Nanopowders (0.5 vol% TiO2 나노분말을 분산시킨 n형 Bi2(Te0.9Se0.1)3 가압소결체의 열전특성)

  • Park, D.H.;Oh, T.S.
    • Journal of the Microelectronics and Packaging Society
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    • v.20 no.1
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    • pp.15-19
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    • 2013
  • The n-type $Bi_2(Te_{0.9}Se_{0.1})_3$ powders, which were fabricated by melting/grinding method and dispersed with 0.5 vol% $TiO_2$ nanopowders, were hot-pressed in order to investigate the effects of $TiO_2$ dispersion on the thermoelectric properties of the hot-pressed $Bi_2(Te_{0.9}Se_{0.1})_3$. Excellent thermoelectric properties such as a maximum figure-of-merit of $2.93{\times}10^{-3}/K$ and a maximum dimensionless figure-of-merit of 1.02 were obtained for the hot-pressed $Bi_2(Te_{0.9}Se_{0.1})_3$. With dispersion of 0.5 vol% $TiO_2$ nanopowders, the maximum figure-of-merit and the maximum dimensionless figure-of-merit decreased to $2.09{\times}10^{-3}/K$ and 0.68, respectively.

An Analysis of the Figure of Merit depending on the cut-off size of a Small Reflector for Satellite Broadcast Receiving Antenna (위성방송 수신용 소형 반사면 안테나의 절단 크기에 따른 성능지수의 분석)

  • Lim, Gye-jae
    • The Journal of Korea Institute of Information, Electronics, and Communication Technology
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    • v.6 no.3
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    • pp.152-155
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    • 2013
  • In this paper, the reduction of the figure of merit depending on the increased spill-over when the parabolic reflector is cut off partially for low-profile configuration in the satellite broadcast receiving antenna is analyzed. Also for the accurate analysis and simulation, it is considered that the noise temperature is increased due to the effect of ground thermal noise toword the sidelobes and back lobes when the antenna is tracked from $0^{\circ}$ to $60^{\circ}$ in elevation angle, and that the total noise temperature is increased because to the noise figure of LNA. As the results, noise temperature is increased up to about 15K and G/T ratio is decreased to about 2.5dB, when the reflector is cut 35% off partially.

Influence of electron irradiation on the structural and optoelectronics properties of ZTZ thin films prepared by magnetron sputtering (마그네트론 스퍼터링법으로 제조된 ZTZ 박막의 구조적 전기광학적 특성에 미치는 전자빔 조사의 영향)

  • Cha, Byung-Chul;Jang, Jin-Kyu;Choi, Jin-Young;Lee, In-Sik;Kim, Dae-Wook;Kim, Yu-Sung;Kim, Daeil
    • Journal of Surface Science and Engineering
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    • v.55 no.6
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    • pp.363-367
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    • 2022
  • Transparent ZnO/Ti/ZnO (ZTZ) tri-layered films were prepared with radio frequency (RF) and direct current (DC) magnetron sputtering on the glass substrate. The thickness of the ZnO and Ti films was kept at 50 and 10 nm to consider the effect of the electron irradiation on the crystallization and optoelectrical properties of the films. From the XRD spectra, post-depostion electron irradiated films showed the characteristic peaks of ZnO(002) and Ti(200), respectively. the observed grain size of the ZnO(002) and Ti(200) enlarged up to 18.27 and 12.16 nm at an irradiation condition of 750 eV. In the figure of merit which means an optoelectrical performance of the films, as deposited films show a figure of merit of 2.0×10-5 𝛺-1, while the films electron irradiated at 750 eV show a higher figure of merit of 5.7×10-5 𝛺-1.

Optimization of Sun-synchronous Spacecraft Constellation Orbits (태양동기궤도 위성군 궤도 최적화에 관한 연구)

  • Kim, Hwayeong;No, Tae Soo;Jung, Okchul;Chung, Daewon;Choi, Jin-Heng
    • Journal of the Korean Society for Aeronautical & Space Sciences
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    • v.43 no.2
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    • pp.141-148
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    • 2015
  • This paper presents a sun-synchronous orbit design which effectuvely includes the requirements derived from spacecraft to ground station contact and spacecraft to target image accessibility. For this purpose, operation parameters of multiple spacecraft are defined as Contact Overlap, Contact Overlap Gap, Access Overlap, Access Overlap Gap. These parameters are used to form a Figure of Merit that reflects the operational requirements. The Figure of Merit is optimized to increase the efficiency of operating multiple spacecraft in constellation and is used to determine the operational orbit of each spacecraft that constitutes the constellation.

Influence of TiO2 Buffer Layer on the Electrical and Optical Properties of IGZO/TiO2 Bi-layered Films (TiO2 완충층이 IGZO/TiO2 이중층 박막의 전기적, 광학적 성질에 미치는 영향)

  • Moon, Hyun-Joo;Kim, Daeil
    • Journal of the Korean Society for Heat Treatment
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    • v.28 no.6
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    • pp.291-295
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    • 2015
  • IGZO single layer and $IGZO/TiO_2$ bi-layered films were deposited on glass substrate at room temperature with radio frequency magnetron sputtering to investigate the effect of $TiO_2$ buffer layer on the electrical and optical properties of the films. For all deposition, the thickness of IGZO and $TiO_2$ Buffer layer was kept at 100 and 5 nm, respectively. In a comparison of figure of merit, IGZO films with a 5-nm-thick $TiO_2$ buffer layer show the higher figure of merit ($8.40{\times}10^{-5}{\Omega}^{-1}$) than that of the IGZO single layer films ($6.23{\times}10^{-5}{\Omega}^{-1}$) due to the enhanced optical transmittance and the decreased sheet resistance of the films. The observed results mean that a 5 nm thick $TiO_2$ buffer layer in the $IGZO/TiO_2$ films results in better electrical and optical performance than conventional IGZO single layer films.

Recent Advances in Thermoelectric Power Generation Technology

  • Sharma, Ashutosh;Lee, Jun Hyeong;Kim, Kyung Heum;Jung, Jae Pil
    • Journal of the Microelectronics and Packaging Society
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    • v.24 no.1
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    • pp.9-16
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    • 2017
  • Thermoelectric power generation (TEG) technology with high figure of merit (ZT) has become the need of the modern world. TEG is a potent technology which can tackle most of the environmental issues such as global warming, change in climatic conditions over the globe, and for burning out of various resources of non-renewable energy like as petroleum deposits and gasolines. Although thermoelectric materials generally convert the heat energy from wastes to electricity according to the theories Seebeck and Peltier effects yet they have not been fully exploited to realize their potential. Researchers are focusing mainly on how to improve the current ZT value from 1 to 2 or even 3 by various approaches. However, a higher ZT value is found to be difficult due to complex thermoelectric properties of materials. Hence, there is a need for developing materials with high figure of merit. Recently, various nanotechnological approaches have been incorporated to improve the thermoelectric properties of materials. In this review paper, the authors have performed a thorough literature survey of various kinds of TEG technology.

Study on Metalizing 2% Na-PbTe for Thermoelectric Device (고효율 열전소재 2%Na-PbTe 의 소자화에 관한 연구)

  • Kim, Hoon;Kang, Chanyoung;Hwang, Junphil;Kim, Woochul
    • Transactions of the Society of Information Storage Systems
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    • v.10 no.2
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    • pp.32-38
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    • 2014
  • Heat emission from the laser diode used in the optical disc drive and the defects from the increased temperature at the system have attracted attentions from the field of the information storage device. Thermoelectric refrigerator is one of the fine solutions to solve these thermal problems. The refrigeration performance of thermoelectric device is dependent on the thermoelectric material's figure-of-merit. Meanwhile, high electrical contact resistivity between metal electrode and p- and n-type thermoelectric materials in the device would lead increased total electrical resistance resulting in the degeneracy in performance. This paper represents the manufacturing process of the PbTe-based material which has one of the highest figure-of-merit at medium-high-temperature, ~ 600K to 900 K, and the nickel contact layer for reduced electrical contact resistance at once, and the results showing the decent contact structure and figure-of-merit even after the long-term operation environment.

Response Analysis of the NE213-PSD System for Neutron Energy Spectreum Measurement (중성자 에너지 측정을 위한 NE213-PSD 장치의 감응 분석)

  • Lee, Kyung-Ju
    • Analytical Science and Technology
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    • v.5 no.4
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    • pp.367-372
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    • 1992
  • In order to measure the energy spectrum of a radioactive neutron source, the pulse shape discrimination (PSD) system with organic scintillator, NE-213, was characterized by using some of the gamma ray sources and neutron source, Am-Be. The figure of merit of the rise time spectrum of AmBe source measured by this system was about 1.13. This value agrees well with the value of 1.3 which is measured for monoenergetic source, $^{12}C(d,\;n)^{13}N$. The results of present experiment for performance test of NE213-PSD system will provide the useful technique to measure the spectrum of neutron-gamma mixed field and to establish the neutron energy spectrum and flux density standards.

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