• 제목/요약/키워드: breakdown electric field

검색결과 391건 처리시간 0.027초

극저온 전력케이블을 액체질소에 대한 방전특성에 관한 연구 (A study on the discharge characteristics of liquid nitrogen using at cryogenic cable)

  • 이현동;주재현;박원주;이광식;이동인
    • 한국조명전기설비학회:학술대회논문집
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    • 한국조명전기설비학회 1996년도 추계학술발표회논문집
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    • pp.125-129
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    • 1996
  • This study describes that electrical breakdown of liquid nitrogen which is influenced with bubble has been investigated as liquid nitrogen is used coolant of high temperature(T/sub c/) superconductivity. In order to investigate breakdown of liquid nitrogen, we formed electrode system of parallel and vertical configuration toward gravitutional direction. In case of changing with electrode configuration of equal electrode and gap spacing in uniform and nonuniform electric field bubble behavior is changed. In result of that, breakdown voltage is changed. Therefore, this study proved that electrode configuration must be formed the smallest existing probability of bubble between two electrodes in order to increase breakdown strength of liquid nitrogen at atmosphere pressure.

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Aspects of Hard Breakdown Characteristics in a 2.2-nm-thick $SiO_2$ Film

  • Komiya, Kenji;Omura, Yasuhisa
    • JSTS:Journal of Semiconductor Technology and Science
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    • 제2권3호
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    • pp.164-169
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    • 2002
  • This paper mainly discusses the hard breakdown of 2.2-nm-thick $SiO_2$ films. It is shown that the hard breakdown event of a 2.2-nm-thick $SiO_2$ film greatly depends on the applied electric field. It is strongly suggested that the local weak spots created by applying a low initial stress to a 2.2-nm-thick $SiO_2$film resist the onset of hard breakdown. In other words, it is anticipated that the stored electrostatic energy is fast dissipated by trap-assisted tunneling in 2.2-nm-thick $SiO_2$ film. Consequently, it is strongly suggested that 2.2-nm-thick $SiO_2$ films are intrinsically quite robust.

InP 다이오드에서 항복전압의 해석적 모델 (Analytical Model for Breakdown Voltages of InP Diodes)

  • 정용성
    • 전자공학회논문지 IE
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    • 제44권1호
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    • pp.10-14
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    • 2007
  • InP의 전자와 정공의 이온화계수로부터 추출한 유효이온화계수를 이용하여 InP 다이오드의 항복전압을 위한 해석적 표현식을 유도하였다. 해석적 항복전압 결과를 $N_D=6\times10^{14}cm^{-3}\sim3\times10^{17}cm^{-3}$의 도핑 농도에서 수치적 결과 및 실험 결과와 비교하였다. 각 농도에 따른 해석적 항복전압은 수치 해석적 결과와 매우 잘 일치하였고, 실험 결과와는 10% 이내의 오차로 잘 일치하였다.

불평등전계 중에서 $SF_{6}-N_{2}$ 혼합기체의 절연파괴 특성 (Breakdown Characteristics of $SF_{6}-N_{2}$ Mixtures in Nonuniform electric Field)

  • 이복희;이경옥
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 2000년도 하계학술대회 논문집 C
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    • pp.1999-2001
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    • 2000
  • Impulse breakdown voltage characteristics of sulphur-hexafluoride/nitrogen ($SF_{6}-N_{2}$) mixtures were presented. The applied voltages were the positive and negative lightning impulse (1.2/44${\mu}s$) and oscillating impulse ($0.4{\mu}s$/2.08MHz) voltages. The predischarge current was observed to clarify the breakdown mechanism. The electrode system was consisted of plane to plane configuration with a needle-shaped protrusion whose length and diameter are 10mm and 1mm. The measurements were carried out at the gas pressure of mixtures up to 0.5MPa with nitrogen concentrations varying from 5 to 20%. The electrical breakdown in $SF_{6}-N_{2}$ mixtures develops with steplike pulses in leader mechanism. The minimum breakdown voltages for the negative lightning and oscillating impulse voltages were higher than those for the positive.

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Effect of Amino Silane Coupling Agent on the AC Electrical Breakdown Phenomena of Epoxy/Layered Silicate Nanocomposite in Needle-plate Electrodes

  • Park, Jae-Jun
    • Transactions on Electrical and Electronic Materials
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    • 제13권3호
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    • pp.149-152
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    • 2012
  • The effects of amino silane coupling agent on the AC electrical treeing and breakdown behaviors in an epoxy/layered silicate (1 wt%) were examined in needle-plate electrode geometry. A layered silicate was exfoliated in an epoxy base resin by using our AC electric field apparatus. To measure the tree initiation and propagation and the breakdown rate, an alternating current (AC) of 10 kV (60 Hz) was applied to the specimen in needle-plate electrode arrangement with a $30^{\circ}C$ insulating oil bath. In the epoxy/amino silane system, the tree initiation time was 11.5 times higher and the breakdown time was 17.9 times higher than those of the neat epoxy resin. The tree initiation time in the epoxy/layered silicate (1 wt%) system with the amino silane was 2.0 times higher, and the breakdown time was 1.5 times higher than those of the epoxy/layered silicate (1 wt%) system.

온도변화에 따른 $SF_{6}/N_{2}$ 혼합가스의 절연특성 (Breakdown Characteristics of $SF_{6}/N_{2}$ Gas Mixtures According to a change in Temperature)

  • 이복희;이봉;최종혁;백영환;정동철;김성원
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 2007년도 제38회 하계학술대회
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    • pp.1455-1456
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    • 2007
  • This paper presents the experimental results on impulse breakdown characteristics under a highly non-uniform electric field in $SF_{6}/N_{2}$ gas mixtures according to a change in temperature. Test temperature ranges from $-25^{\circ}C$ to $25^{\circ}C$. The impulse predischarge breakdown developments are investigated by the measurements of current pulse and discharge luminous events. As a result, the predischarge development mechanisms for both positive and negative polarities are same. When increasing the temperature, breakdown voltage due to lightning impulse voltage is increased in negative polarity. On the other hand, when increasing the temperature, breakdown voltage due to lightning impulse voltage is not changed in positive polarity.

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사이리스터의 결함과 항복전압의 관계 분석 (Analysis of the relationship between breakdown voltage and defect of thyristor)

  • 이양재;서길수;김형우;김기현;김상철;김남균;김병철
    • 한국전기전자재료학회:학술대회논문집
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    • 한국전기전자재료학회 2005년도 하계학술대회 논문집 Vol.6
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    • pp.149-150
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    • 2005
  • Thyristor breakdown voltage variation acceleration aging test was investigated. The breakdown voltage was deceased after 1000 hours acceleration aging test. It temperature rising caused by electric field concentration at the edge beveling region of the thyristor was confirmed using Silvaco device simulation. The local temperature rising is driving force for the defect propagation. Consequently, propagated defects of the beveling region seems to decrease thyristor's breakdown voltage.

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불평등전계중에서 과도과전압에 대한 $SF_{6}$가스의 절연특성 (Dielectric Characteristics of $SF_{6}$ Gas Stressed by VFTO in Inhomogeneous Field)

  • 이복희;이창준;길경석;안창환
    • 한국전기전자재료학회:학술대회논문집
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    • 한국전기전자재료학회 1995년도 추계학술대회 논문집
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    • pp.306-309
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    • 1995
  • This paper describes the dielectric characteristics of $SF_{6}$ gas in a non-uniform electric field under overvoltages. The breakdown voltage-time characteristics and the breakdown voltage-gas pressure characteristics are measured within a gas pressure range extending from 0.1 to 0.5 [Mpa] for the plane electrode system with a needle-shaped protrusion. The curvature radius of the needle protrusion is 0.5[mm]. Also, the growth process of the predischarge are simultaneously observed. As a result, it is found that the breakdown mechanism and predischarge phenomena are closely associated with the polarity and waveforms of the testing voltage.

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질화와 재산화 조건에 따른 모스 소자의 전기적 특성변화 (Electrical properties variations of nitrided, reoxided MOS devices by nitridation condition)

  • 이정석;이용재
    • 대한전자공학회:학술대회논문집
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    • 대한전자공학회 1998년도 하계종합학술대회논문집
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    • pp.343-346
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    • 1998
  • Ultra-thin gate oxide in MOS devices are subjected to high-field stress during device operation, which degrades the oxide and exentually causes dielectric breakdown. In this paper, we investigate the electrical properties of ultra-thin nitrided oxide (NO) and reoxidized nitrided oxide(ONO) films that are considered to be promising candidates for replacing conventional silicon dioxide film in ULSI level integration. We study vriations of I-V characteristics due to F-N tunneling, and time-dependent dielectric breakdown (TDDB) of thin layer NO and ONO depending on nitridation and reoxidation condition, and compare with thermal $SiO_{2}$. From the measurement results, we find that these NO and ONO thin films are strongly depending on its condition and that optimized reoxided nitrided oxides (ONO) films show superior dielectric characteristics, and breakdown-to-change ( $Q_{bd}$ ) performance over the NO films, while maintaining a similar electric field dependence compared to NO layer.

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P-Emitter의 길이, 구조가 Asymmetric SiC MOSFET 소자 성능에 미치는 영향 (Effect of P-Emitter Length and Structure on Asymmetric SiC MOSFET Performance)

  • 김동현;구상모
    • 한국전기전자재료학회논문지
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    • 제33권2호
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    • pp.83-87
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    • 2020
  • In this letter, we propose and analyze a new asymmetric structure that can be used for next-generation power semiconductor devices. We compare and analyze the electrical characteristics of the proposed device with respect to those of symmetric devices. The proposed device has a p-emitter on the right side of the cell. The peak electric field is reduced by the shielding effect caused by the p-emitter structure. Consequently, the breakdown voltage is increased. The proposed asymmetric structure has an approximately 100% higher Baliga's figure of merit (~94.22 MW/㎠) than the symmetric structure (~46.93 MW/㎠), and the breakdown voltage of the device increases by approximately 70%.