• Title/Summary/Keyword: Joule heating

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Joule Heating Effects and Initial Resistance in Electromigration Test (EM시험에서의 Joule Heating 영향 및 초기저항값)

  • Ju, Cheol-Won;Gang, Hyeong-Gon;Han, Byeong-Seong
    • The Transactions of the Korean Institute of Electrical Engineers C
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    • v.48 no.6
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    • pp.436-441
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    • 1999
  • Joule heating effect in EM(Electromigration) test were performed on a bend test structure. EM test is done under high current densities(1.0-2.5MA/cm2), which leads to joule heating. Since joule heating is added to the controlled oven(stress) temperature, themetal line temperature is higher than the stress temperature. The increase in the stress temperature due to joule heating is important because EM phenomena and metal line failure are related to the stress temperature. In this paper, metal line was stressed with a current density of 1.0 MA/$cm^2$, 1.5MA/$cm^2$, 2.0MA/$cm^2$, 2.5MA/$cm^2$, for 1200 sec and temperature increase due to joule heating was less than $10^{\circ}C$. Also it took 30 minutes for the metal line to equalized with oven temperature. Recommendations are given for the EM test to determine the initial resistance of EM test structure under stress temperature and current density.

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Low Temperature Growth of High-Quality Carbon Nanotubes by Local Surface Joule Heating without Heating Damage to Substrate

  • Heo, Sung-Taek;Lee, Dong-Gu
    • Carbon letters
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    • v.10 no.3
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    • pp.230-233
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    • 2009
  • In this study, a low temperature growth of high-quality carbon nanotubes on glass substrate using a local surface heating without heating damage to substrate was tried and characterized. The local joule heating was induced to only Ni/Ti metal film on glass substrate by applying voltage to the film. It was estimated that local surface joule heating method could heat the metal surface locally up to around $1200^{\circ}C$ by voltage control. We could successfully obtain high-quality carbon nanotubes grown at $300^{\circ}C$ by applying 125 V for joule heating as same as carbon nanotubes grown at $900^{\circ}C$.

Crystallization Mechanisms of Joule-Heating-Induced Crystallization

  • Park, Doo-Jung;Ro, Jae-Sang
    • Journal of Information Display
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    • v.10 no.2
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    • pp.76-79
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    • 2009
  • In Joule-heating-induced crystallization, solid-to-solid or liquid-to-solid phase transformation could occur. It was found that novel physical phenomena that randomly nucleated liquid seeds, followed by rapid solidification in an amorphous matrix, during the Joule-heating-up period play an important role especially in liquid-to-solid transformation. Under some processing conditions, super-grains sized 6-8 ${\um}m$ were produced by the lateral growth from the initial seeds, without any artificially control.

Study and Industrialization on the Joule Heating in Japan (일본의 쥴가열에 대한 연구 및 산업화)

  • Lee, Nam-Hyouck;Kim, Young-Ho
    • Bulletin of Food Technology
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    • v.22 no.4
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    • pp.808-815
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    • 2009
  • Joule heating은 내부 가열법 중의 하나이며, Ohm의 법칙에 따라서 식품에 직접전기를 통전하여 식품이 갖고 있는 전기저항성에 의해서 식품자체를 자기 발열시키는 가열방법이다. 따라서 Joule 가열을 Ohmic heating 또는 통전가열이라고도 부르고 있다. 열전달성이 느린 고형물 또는 고점도의 Paste형 식품도 어느 정도 전도성이 있으면 신속하면서도 균일하게 열처리를 할 수 있다. 최근 일본에서는 통전가열에 대한 연구가 활발히 진행 중에 있으며, Joule 가열 연구 및 산업화 동향의 일부를 소개하고자 한다.

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Crystallization of Amorphous Silicon Films Using Joule Heating

  • Ro, Jae-Sang
    • Journal of the Korean institute of surface engineering
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    • v.47 no.1
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    • pp.20-24
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    • 2014
  • Joule heat is generated by applying an electric filed to a conductive layer located beneath or above the amorphous silicon film, and is used to raise the temperature of the silicon film to crystallization temperature. An electric field was applied to an indium tin oxide (ITO) conductive layer to induce Joule heating in order to carry out the crystallization of amorphous silicon. Polycrystalline silicon was produced within the range of a millisecond. To investigate the kinetics of Joule-heating induced crystallization (JIC) solid phase crystallization was conducted using amorphous silicon films deposited by plasma enhanced chemical vapor deposition and using tube furnace in nitrogen ambient. Microscopic and macroscopic uniformity of crystallinity of JIC poly-Si was measured to have better uniformity compared to that of poly-Si produced by other methods such as metal induced crystallization and Excimer laser crystallization.

Joule-heating induced crystallization (JIC) of amorphous silicon films

  • Hong, Won-Eui;Lee, Joo-Yeol;Kim, Bo-Kyung;Ro, Jae-Sang
    • 한국정보디스플레이학회:학술대회논문집
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    • 2007.08a
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    • pp.459-462
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    • 2007
  • An electric field was applied to a conductive layer to induce Joule heating in order to carry out the crystallization of amorphous silicon. Polycrystalline silicon was produced through a solid state transformation within the range of a millisecond. Uniformly distributed grains were obtained due to enormously high heating rate.

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A Study on Joule Heating Simulation Method to Prevent Sensitivity Current Trip of Electric Vehicle Charger (전기자동차 충전기의 누전차단기 감도 전류 Trip 방지를 위한 Joule Heating 시뮬레이션 방안연구)

  • Lee, Beoung-Kug;Eo, Ik-soo
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.22 no.4
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    • pp.150-159
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    • 2021
  • This study aimed to prevent inconvenience to electric vehicle users caused by an interruption of charging by the earth leakage breaker trip that occurs during charging. As a field case study, it was confirmed that during the battery charger failure type, leakage current measurement experiment by vehicle type, and leakage current breaker operation experiment, the internal temperature of the charger rose to more than 60 ℃ in summer, and the earth leakage circuit breaker stopped charging by tripping at 80% of the rated sensitivity current. Through Joule heating modeling, 32A is energized at the reference temperature of 30 ℃ at the initial time t=0 (s). After t=3000 (s), the heat generated around the charging part of the earth leakage breaker increased to 32.4 ℃. The temperature and time factors correlated with the amount of heat generated according to the statistical verification tool with a correlation coefficient of 0.97. Overall, it is possible to prevent the leakage breaker sensitivity current trip due to an increase in temperature inside the charger in summer by performing a Joule heating simulation according to the material of the charging case, the arrangement of the internal wiring, and the dielectric medium when developing the charger device.

Effect of Joule Heating Variation on Phonon Heat Flow in Thin Film Transistor (줄 가열 변화에 따른 박막 트랜지스터 내 포논 열 흐름에 대한 수치적 연구)

  • Jin, Jae-Sik;Lee, Joon-Sik
    • Transactions of the Korean Society of Mechanical Engineers B
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    • v.33 no.10
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    • pp.820-826
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    • 2009
  • The anisotropic phonon conductions with varying Joule heating rate of the silicon film in Silicon-on-Insulator devices are examined using the electron-phonon interaction model. It is found that the phonon heat transfer rate at each boundary of Si-layer has a strong dependence on the heating power rate. And the phonon flow decreases when the temperature gradient has a sharp change within extremely short length scales such as phonon mean free path. Thus the heat generated in the hot spot region is removed primarily by heat conduction through Si-layer at the higher Joule heating level and the phonon nonlocality is mainly attributed to lower group velocity phonons as remarkably dissimilar to the case of electrons in laser heated plasmas. To validate these observations the modified phonon nonlocal model considering complete phonon dispersion relations is introduced as a correct form of the conventional theory. We also reveal that the relation between the phonon heat deposition time from the hot spot region and the relaxation time in Si-layer can be used to estimate the intrinsic thermal resistance in the parallel heat flow direction as Joule heating level varies.

Joule Heating of Metallic Nanowire Random Network for Transparent Heater Applications

  • Pichitpajongkit, Aekachan;Eom, Hyeonjin;Park, Inkyu
    • Journal of Sensor Science and Technology
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    • v.29 no.4
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    • pp.227-231
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    • 2020
  • Silver nanowire random networks are promising candidates for replacing indium tin oxide (ITO) as transparent and conductive electrodes. They can also be used as transparent heating films with self-cleaning and defogging properties. By virtue of the Joule heating effect, silver nanowire random networks can be heated when voltage bias is applied; however, they are unsuitable for long-term use. In this work, we study the Joule heating of silver nanowire random networks embedded in polymers. Silver nanowire random networks embedded in polymers exhibit breakdown under the application of electric current. Their surface morphological changes indicate that nanoparticle formation may be the main cause of this electrical breakdown. Numerical analyses are used to investigate the temperatures of the silver nanowire and substrate.

LCD with Tunable Viewing Angle by Thermal Modulation of Optical Layer

  • Gwag, Jin-Seog;Lee, You-Jin;Han, In-Young;Yu, Chang-Jae;Kim, Jae-Hoon
    • Journal of Information Display
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    • v.10 no.1
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    • pp.19-23
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    • 2009
  • In this paper, we review the proposed liquid crystal display (LCD) with a tunable viewing angle consisting of a conventional liquid crystal display (LCD) panel and a thermally variable retardation layer (TVRL) characterized by uniformly aligned LC film with transparent indium-tin-oxide electrodes for Joule heating. In the TVRL, nematic phase is transitioned into isotropic by Joule heating. The numerical calculation showed that the intrinsic wide viewing angle was achieved at the isotropic phase of the TVRL by Joule heating, whereas the narrow viewing angle was obtained at the nematic phase of the TVRL. The simulated and experimental results of the proposed LCD show continuous and symmetrical viewing angle characteristics by tuning the retardation of TVRL using Joule heating. The structure of the viewing angle control proposed here is adoptable to all LCD modes with wide viewing angle characteristics.