• 제목/요약/키워드: Thermal capacitance

검색결과 205건 처리시간 0.022초

고온에서 Pd 전극의 형태가 수소 센서의 감도에 미치는 영향 (Effect on the Sensitivity of a Hydrogen Sensor by Pd Electrode Patterns at High Temperature)

  • 김성진
    • 전기전자학회논문지
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    • 제22권2호
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    • pp.356-361
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    • 2018
  • 고온에서 이용 가능한 수소 센서에 관해 연구하였다. 센서는 $Pd/Ta_2O_5/SiC$으로 구성된 MOS 구조로 제작되었으며, $Ta_2O_5$ 박막은 급속 열 산화법(RTO)법으로 형성하였다. 본 연구에서는 3가지 다른 패턴의 팔라듐(Pd) 전극으로 만든 센서를 제작하여, Pd 전극의 형태가 응답 특성에 미치는 영향을 고찰하였다. 그 결과, 센서는 Pd 전극의 채워진 면적이 클수록, 정전용량의 응답특성이 개선됨을 확인하였다.

철도차량 견인전동기의 가속열화수명평가 기술현황 (A technology State of Accelerating Degradation and Life Estimation on the Traction Motor for Railway Rolling Stock)

  • 왕종배;김기준;최영찬
    • 한국전기전자재료학회:학술대회논문집
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    • 한국전기전자재료학회 2000년도 제2회 학술대회 논문집 일렉트렛트 및 응용기술전문연구회
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    • pp.25-28
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    • 2000
  • In this paper, the technology for accelerating degradation & life estimation on the traction motor was introduced with the stator form-winding sample coils of the 200 Class insulation system The accelerative degradation was performed in 10 cycles, which were composed of thermal stress, fast rising surge voltage, vibration, water immersion and overvoltage applying. After aging of 10 cycles, condition diagnosis test such as insulation resistance & polarization index, capacitance & dielectric loss and partial discharge properties were investigated in the temperature range of $20{\sim}160^{\circ}C$. Relationship between degradation conditions and diagnosis results were analyzed to find an dominative degradation factor at the end-life point

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Threshold Voltage Properties of OFET with CuPc Active Material

  • Lee, Ho-Shik;Kim, Seong-Geol
    • Journal of information and communication convergence engineering
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    • 제13권4호
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    • pp.257-263
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    • 2015
  • In this study, organic field-effect transistors (OFETs) using a copper phthalocyanine (CuPc) material as an active layer and SiO2 as a gate insulator were fabricated with varying active layer thicknesses and channel lengths. Further, using a thermal evaporation method in a high-vacuum system, we fabricated a CuPc FET device of the top-contact type and used Au materials for the source and drain electrodes. In order to discuss the channel formation and FET characteristics, we observed the typical current-voltage characteristics and calculated the threshold voltage of the CuPc FET device. We also found that the capacitance reached approximately 97 pF at a negative applied voltage and increased upon the accumulation of carriers at the interface of the metal and the CuPc material. We observed the typical behavior of a FET when used as an n-channel FET. Moreover, we calculated the threshold voltage to be about 15-20 V at VDS = -80 V.

염분에 따른 변압기유의 유전특성 (I) (The Dielectric Characteristics of Transformer Oil due to the Sodium Chloride (I))

  • 조경순;송병기;이수원;신종열;홍진웅
    • 한국전기전자재료학회:학술대회논문집
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    • 한국전기전자재료학회 1996년도 춘계학술대회 논문집
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    • pp.206-210
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    • 1996
  • In order to investigate the electrical properties for transformer oils which contains a Pure sodium chloride, the dielectric properties is made researches. To measure the dielectric loss of specimen, a coaxial cylindrical liquid electrode is used, and its geometric capacitance is confirmed to 16[pF]. And the dielectric dissipation factor, tan$\delta$, is measured by using the Video Bridge 2150. The thermal static oven with an automatically static temperature controller is used so as to support specific temperature to the specimen. This experiments for measuring the dielectric lass is performed at 20-120[$^{\circ}C$] in the temperature range, 30∼1.5x10$\^$5/[Hz] in the frequency range and 300∼1500[mV] in the voltage range. The result of experiment for the movement of carrier and the physical constants to contribute dielectric properties of specimen with a pure sodium chloride.

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Study on Electrical Characteristics of Chloromethylated Polyimide

  • Yu, I.H.;Zhong, Z-X;Lee, M.H.;Lee, S.H.
    • 한국정보디스플레이학회:학술대회논문집
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    • 한국정보디스플레이학회 2005년도 International Meeting on Information Displayvol.I
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    • pp.472-475
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    • 2005
  • The electrical performances of liquid crystal (LC) cells with chloromethylated polyimide (CMPI) alignment layers were investigated. The CMPI layer was previously reported as a multifunctional layer that does role of LC alignment and planarization layer as well as photo-alignment material with high photosensitivity and excellent thermal stability. The capacitance-voltage (C-V) characteristics of LC cells with CMPI alignment layers were measured. Mechanical rubbing of the CMPI layer did not generate much difference in residual DC when compared to commercial PI. However, the LC cell with photo-oxidation CMPI layer shows a high residual DC value and a corresponding low voltage holding ratio (VHR) due to the photo-induced ionic charges on the alignment layer.

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One-Chip 마이크로프로세서를 이용한 Nd:YAG 레이저의 반복율 및 펄스폭제어 (The Repetition rate and Pulse-width control of Nd:YAG laser using One-Chip Microprocessor)

  • 홍정환;정영환;양동민;김휘영;김희제
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 1998년도 하계학술대회 논문집 E
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    • pp.1696-1698
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    • 1998
  • Pulsed Nd:YAG laser using Nd:YAG crystal operates stably in the thermal conductivity, mechanical, optical condition. That is used broadly in material processings because of easy reaction to the materials, and the maintenance is very easy because of lamp excitation. In these material processings, power dinsity control is very important to improve processing technology. Power density is controled by inductance and capacitance or repetition rate. Therefore we are going to control laser power density as One-Chip Microprocessor(PIC16C55) and 8051. We have been experimented at the pulse repetition rate range of 10pps to 60pps(pulse per second).

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공통모드 노이즈 저감을 위한 전력전자모듈

  • 신종원
    • 전력전자학회:학술대회논문집
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    • 전력전자학회 2018년도 전력전자학술대회
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    • pp.336-337
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    • 2018
  • 전력 전자 시스템 내의 전도성 노이즈는 반도체 스위칭 소자의 고속 동작에 큰 영향을 받는다. 특히 실리콘 카바이드 (SiC) 등의 신소재 반도체 소자 (wide band-gap device, WBG device) 특유의 고속 dv/dt 특성이 전력전자모듈 (power electronics module, PEM) 내의 기생 용량 (parasitic capacitance)에 인가될 경우 상당한 전도성 노이즈의 원인이 되므로 이를 해결할 필요가 있다. 본 논문에서는 유전율이 낮은 재료를 PEM 내부에 사용함으로써 기생 용량을 줄이고, 따라서 공통 모드 전류의 발생 또한 최소화할 수 있는 설계를 제안한다. 제안된 PEM 설계 기법은 외부 필터를 필요로 하지 않으며, PEM 내의 스위칭 소자-방열 소자간 열저항 (thermal resistance)를 증가시키지 않으면서도 기생 용량을 최소화하여 노이즈를 억제한다. 제안된 방법으로 제작된 PEM을 1 kW 출력 100 kHz 스위칭 주파수의 강압형 dc-dc 컨버터에 적용하여 공통모드 전도성 전류가 줄어듬을 증명하였다.

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산화막 및 재산화질화산화막의 MOS 캐패시터와 MOSFET의 신뢰성 (Reliability of MOS Capacitors and MOSFET's with Oxide and Reoxidized-Nitrided-Oxide as Gate Insulators)

  • 노태문;이경수;유병곤;남기수
    • 전자공학회논문지A
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    • 제30A권11호
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    • pp.105-112
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    • 1993
  • Oxide and reoxidized-nitrided-oxide were formed by furnace oxidation and rapid thermal processing (RTP). MOS capacitor and n-MOSFET's with those films as gate insulators were fabricated. The electrical characteristics of insulators were evaluated by current-voltage, high-frequency capacitance-voltage (C-V), and time-dependent dielectrical breakdown (TDDB) measurements. The hot carrier effects of MOSFET's were also investigated. Time-dependent dielectrical breakdown (TDDB) characteristics show that the life time of reoxidized-nitrided-oxide films is about 3 times longer than that of oxides. Hot carrier effects reveal that the life time of MOSFET's with reoxidized-nitrided-oxides is about 3 times longer than that of MOSFET's with oxides. Therefore, it is found that the reliability of dielectric films estimated by the hot carrier effects of MOSFET's is consistent with that of dielectric films from TDDB method.

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차량용 연료전지 스택의 절연열화 진단을 위한 원통형 정전용량-전기전도도 센서개발 (Development of Cylindrical Capacitive-Conductive Sensor to Evaluate Insulating Degradation for FCEV Stack)

  • 김재훈;김주한;김윤형;최강월;한상옥;용기중
    • 전기학회논문지P
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    • 제59권3호
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    • pp.317-324
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    • 2010
  • It was used as measuring system to diagnose insulating condition, by which was kept a insulating resistance of inner stack and at the same time was cooled electrochemical heat of reaction of FCEV(fuel cell electric vehicle) stack that used a compressed hydrogen gas reacting with oxygen in accordance with variation on thermal degradation of nonconductive heat transfer fluid. Consequently it was developed a cylindrical multi-terminal capacitive-conductive sensor that could be attached to the internal surface of cooling system pipe to evaluate capacitance and conductivity of heat transfer fluid.

저온 래디컬 산화법에 의한 고품질 초박막 게이트 산화막의 성장과 이를 이용한 고성능 실리콘-게르마늄 이종구조 CMOS의 제작 (High Quality Ultrathin Gate Oxides Grown by Low-Temperature Radical Induced Oxidation for High Performance SiGe Heterostructure CMOS Applications)

  • 송영주;김상훈;이내응;강진영;심규환
    • 한국전기전자재료학회논문지
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    • 제16권9호
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    • pp.765-770
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    • 2003
  • We have developed a low-temperature, and low-pressure radical induced oxidation (RIO) technology, so that high-quality ultrathin silicon dioxide layers have been effectively produced with a high reproducibility, and successfully employed to realize high performace SiGe heterostructure complementary MOSFETs (HCMOS) lot the first time. The obtained oxide layer showed comparable leakage and breakdown properties to conventional furnace gate oxides, and no hysteresis was observed during high-frequency capacitance-voltage characterization. Strained SiGe HCMOS transistors with a 2.5 nm-thick gate oxide layer grown by this method exhibited excellent device properties. These suggest that the present technique is particularly suitable for HCMOS devices requiring a fast and high-precision gate oxidation process with a low thermal budget.