• Title/Summary/Keyword: Breakdown

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Short Channel n-MOSFET의 Breakdown 전압

  • Kim, Gwang-Su;Lee, Jin-Hyo
    • ETRI Journal
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    • v.9 no.1
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    • pp.118-124
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    • 1987
  • Short channel n-MOSFET의 드레인-소오스 사이의 breakdown은 단순한 접합 breakdown이 아닌 avalanche-induced breakdown으로 p-MOSFET, long channel n-MOSFET의 breakdown 전압보다 훨씬 작은 값을 갖는다. Short channel n-MOSFET의 breakdown의 특징은 current-controlled 부저항 특성(snapback)이 나타나고, 게이트 전압에 따라 breakdown 전압보다 작은 sustainning 전압이 존재한다. 이와 같은 sustainning 전압은 short channel n-MOSFET의 안정한 동작에 또 하나의 제한 요소가 될 수 있다. 따라서 공정 및 회로 시뮬레이션을 위해, short channel n-MOSFET의 avalanche breakdown 현상에 대한 정확한 분석이 요구된다. Short channel n -MOSFET의 avalanche breakdown 현상을 분석하기 위해서Parasitic bipolar transistor를 도입한 분석적 모델을 이용하였다.

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Electrical Breakdown Properties of Insulating Oils for oil-immersed transformer (유입변압기용 절연유의 절연파괴특성)

  • 이인성;신현택;이종필;이수원;홍진웅
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • pp.605-608
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    • 2001
  • With the intention of investigating the breakdown properties of oil-immersed transformer oils in temperature range of 20∼100[$^{\circ}C$], we are made researches AC breakdown in the gap of 500∼2,500[$\mu\textrm{m}$]. The classification for the physical properties of oil for oil-immersed transformer by FTH and $^1$H-NMR experiments was confirmed to type of mineral oils. As the dependance of breakdown properties due to electrode gap length variation, breakdown voltage was found increasing according to the increase of gap, while dielectric strength was decreasing. As a result the characteristics for AC breakdown, It goes to prove that the breakdown voltage was increased to 90[$^{\circ}C$] but decreased over 90[$^{\circ}C$] in the temperature range. Also, breakdown voltage was found increasing in the increase of gap and the rising of temperature according to Weibull distribution.

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Effect of CA Storage Conditions on the Internal Breakdown of Fuji Apple Fruits under CA Storage (Fuji 사과의 CA저장중 저장조건이 과육갈변에 미치는 영향)

  • 이주백;최종욱
    • Korean Journal of Food Preservation
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    • v.4 no.3
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    • pp.227-235
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    • 1997
  • The internal breakdown of Fuji apple during CA storage classified as watercore breakdown, low temperature breakdown and CO2 injury. This study was undertaken to investigate the watercore breakdown injury factors of Korean Fuji apple during CA storage. The development of internal breakdown was more increased with the larger size, the later harvest time and the hither CO2 gas level. But in internal breakdown fruit of the titratable acidity and soluble solid decreased significantly, the pH of fruit juice and the production of carbon dioxide was greatly increased. The best gas levels of CA storage was 2% oxygen and 3% carbon dioxide. Thus, the predictable parameters of internal breakdown of fruit were increase in pH on decrease titratable acidity within 2 months of CA storage, increase carbon dioxide. So, it was found that the best CA sotrage for internal breakdown control of fruit during CA storage was delayed CA storage methods after low temperature storage immediate harvest of apple and than took a step. The delayed CA storage after low temperature storage for 2 months was more effective in the prevention of development of internal breakdown than immediate CA storage after harvest.

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Analysis of Breakdown Voltage Dispersion and Breakdown Process in Mineral Oil (광유 중 절연파괴전압의 분산과 절연파괴진전 과정의 분석)

  • Lim, Dong-Young;Park, Sung-Gyu;Park, Cheol-Ho;Kim, Ki-Chai;Lee, Kwang-Sik;Choi, Eun-Hyeok
    • Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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    • v.29 no.6
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    • pp.35-41
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    • 2015
  • This paper presents a breakdown voltage and a process of breakdown progress in mineral oil under an quasi-uniform field with decomposition products which occur after the oil discharge. The breakdown voltage in the oil revealed the characteristics of dispersion regardless of an electrode gap. The cumulative probability distribution was used to analyze the dispersion of the breakdown voltage. In addition, the process of breakdown progress in the oil can be reasonably described by the electron breakdown theory based on both electrons emitted from the cathode and ions by field-aided dissociation of the oil. The proposed breakdown process will be used for the basic data to explain the behavior pattern of the decomposition product to cause the dispersion of the breakdown voltage.

Diamond Schottky Barrier Diodes With Field Plate (필드 플레이트가 설계된 다이아몬드 쇼트키 장벽 다이오드)

  • Chang, Hae Nyung;Kang, Dong-Won;Ha, Min-Woo
    • The Transactions of The Korean Institute of Electrical Engineers
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    • v.66 no.4
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    • pp.659-665
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    • 2017
  • Power semiconductor devices required the low on-resistance and high breakdown voltage. Wide band-gap materials opened a new technology of the power devices which promised a thin drift layer at an identical breakdown voltage. The diamond had the wide band-gap of 5.5 eV which induced the low power loss, high breakdown capability, low intrinsic carrier generation, and high operation temperature. We investigated the p-type pseudo-vertical diamond Schottky barrier diodes using a numerical simulation. The impact ionization rate was material to calculating the breakdown voltage. We revised the impact ionization rate of the diamond for adjusting the parallel-plane breakdown field at 10 MV/cm. Effects of the field plate on the breakdown voltage was also analyzed. A conventional diamond Schottky barrier diode without field plate exhibited the high forward current of 0.52 A/mm and low on-resistance of $1.71{\Omega}-mm$ at the forward voltage of 2 V. The simulated breakdown field of the conventional device was 13.3 MV/cm. The breakdown voltage of the conventional device and proposed devices with the $SiO_2$ passivation layer, anode field plate (AFP), and cathode field plate (CFP) was 680, 810, 810, and 1020 V, respectively. The AFP cannot alleviate the concentration of the electric field at the cathode edge. The CFP increased the breakdown voltage with evidences of the electric field and potential. However, we should consider the dielectric breakdown because the ideal breakdown field of the diamond is higher than that of the $SiO_2$, which is widely used as the passivation layer. The real breakdown voltage of the device with CFP decreased from 1020 to 565 V due to the dielectric breakdown.

Effect on Metal Guard Ring in Breakdown Characteristics of SiC Schottky Barrier Diode (금속 가드 링이 SiC 쇼트키 다이오드의 항복전압에 미치는 영향)

  • Kim, Seong-Jin
    • Journal of the Korean Institute of Electrical and Electronic Material Engineers
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    • v.18 no.10
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    • pp.877-882
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    • 2005
  • In order to fabricate a high breakdown SiC-SBD (Schottky barrier diode), we investigate an effect on metal guard ring (MGR) in breakdown characteristics of the SiC-SBD. The breakdown characteristics of MGR-type SiC-SBD is significantly dependent on both the guard ring metal and the alloying time of guard ring metal. The breakdown characteristics of MGR-type SiC-SBDs are essentially improved as the alloying time of guard ring metal is increased. The SiC-SBD without MGR shows less than 200 V breakdown voltage, while the SiC-SBD with Al MGR shows approximately 700 V breakdown voltage. The improvement in breakdown characteristics is attributed to the field edge termination effect by the MGR, which is similar to an implanted guard ring-type SiC-SBD. There are two breakdown origins in the MGR-type SiC-SBD. One is due to a crystal defects, such as micropipes and stacking faults, in the Epi-layers and the SiC substrate, and occurs at a lower electric field. The other is due to the destruction of guard ring metal, which occurs at a higher electric field. The demolition of guard ring metal is due to the electric field concentration at an edge of Schottky contact metal.

Electrical Breakdown Properties of Insulating Oils for oil-immersed transformer (유입변압기용 절연유의 절연파괴특성)

  • Lee, I.S.;Shin, H.T.;Lee, J.P.;Lee, S.W.;Hong, J.W.
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • pp.605-608
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    • 2001
  • With the intention of investigating the breakdown properties of oil-immersed transformer oils in temperature range of $20\sim100[^{\circ}C]$, we are made researches AC breakdown in the gap of $500\sim2500[{\mu}m]$. The classification for the physical properties of oil for oil-immersed transformer by FTIR and H-NMR experiments was confirmed to type of mineral oils. As the dependance of breakdown properties due to electrode gap length variation, breakdown voltage was found increasing according to the increase of gap, while dielectric strength was decreasing. As a result the characteristics for AC breakdown, It goes to prove that the breakdown voltage was increased to $90[^{\circ}C]$ but decreased over $90[^{\circ}C]$ in the temperature range. Also, breakdown voltage was found increasing in the increase of gap and the rising of temperature according to Weibull distribution.

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Interfacial Breakdown characteristics in XLPE/EPDM Laminate (XLPE/EPDM laminate의 절연파괴특성)

  • 남진호;서광석
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • pp.495-497
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    • 1999
  • In order to determine what influences the interfacial breakdown in EPDM/XLPE laminates, We made the breakdown test ceil and this was pressure controllable breakdown test cell. We make the needle electrode (tip radius: about 10 micrometer) using electrochemical method. We studied the interfacial silicone oil was higher than that with silicone grease. As a function of heat treatment time in a vacuum, interfacial breakdown strength increased much in XLPE/EPDM laminates pasted with silicone grease but increased a little in that with silicone oil.

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Asymmetric 및 Symmetric MOSFET 소자의 Drain Breakdown 특성 분석

  • Choe, Pyeong-Ho;Kim, Sang-Seop;Choe, Byeong-Deok
    • Proceedings of the Korean Vacuum Society Conference
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    • pp.232.2-232.2
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    • 2013
  • 본 연구에서는 asymmetric과 symmetric MOSFET 소자의 drain breakdown 및 snapback 특성을 분석하였다. 실험에서는 두 MOSFET 소자의 동작 영역에서 게이트와 드레인에 각각 전압을 인가하였다. 드레인 전류-전압 곡선으로 부터 drain breakdown 전압과 snapback 전압을 추출하였다. 결과 avalanche breakdown 발생 전의 드레인 전류는 asymmetric 구조의 경우 더 작은 값을 보였으며 이는 asymmetric 구조에서의 drain field 가 더 낮기 때문이다. 따라서 impact ionization은 asymmetric 구조에서 덜 발생하며, snapback 전압은 avalanche breakdown voltage가 작은 asymmetric 구조에서 크게 나타났다.

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Impacts on the Deteriorative Breakdown Characteristics by the Void of Polyethyleme (Polyethylene의 공극이 절연파괴특성에 미치는 영향)

  • 정영순
    • 전기의세계
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    • v.26 no.3
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    • pp.59-62
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    • 1977
  • This study is to investigate the v-t characteristics gained by means of the Weibull distribution and to analyze the characteritics of fatigue breakdown caused by the A-C voltage of cross-linked polyethylene with and without void. By the results, it has in most cases reveald deteriorative breakdown in case of none-void, and that random breakdown or complex Weibull distribution of deteriorative breakdown and random breakdown in case of with void.

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