• 제목/요약/키워드: conduction ratio

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일축연신에 따른 Polyphenylene sulfide(PPS)의 전기전도 및 광전도 특성 (The Properties of Electrical Conduction and Photoconduction in Polyphenylene Sulfide(PPS) by Uniaxial Elongation)

  • 이운용;장동욱;강성화;임기조;류부형
    • 한국전기전자재료학회:학술대회논문집
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    • 한국전기전자재료학회 1998년도 춘계학술대회 논문집
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    • pp.223-226
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    • 1998
  • In this paper, we have investigated how morphology and electrical properties in Polyphenylene sulfide(PPS) are changed by uniaxial elongation. XRD pattern shows that interplanar distance and crystallinities are decreased by increasing elongation ratio. Electrical conduction mechanism of PPS is explained as schottky emission from analysis of electrical current. The electrical current is decreased by increasing elongation ratio. The conductivity is changed remarkably above the glass transition temperature around $(82^{\circ}C)$. The band gap of PPS is evaluated as 3.9-4(eV) from the results of photoconductivity. Increarnent of elongation ratio gives us some information about deep trap formation from photocurrent.

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비대칭 이중게이트 MOSFET에서 상단과 하단 산화막 두께비가 문턱전압이하 스윙에 미치는 영향 (Influence of Ratio of Top and Bottom Oxide Thickness on Subthreshold Swing for Asymmetric Double Gate MOSFET)

  • 정학기
    • 한국정보통신학회논문지
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    • 제20권3호
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    • pp.571-576
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    • 2016
  • 비대칭 이중게이트 MOSFET는 다른 상하단 게이트 산화막 두께를 갖는다. 상하단 게이트 산화막 두께 비에 대한 문턱전압이하 스윙 및 전도중심의 변화에 대하여 분석하고자한다. 문턱전압이하 스윙은 전도중심에 따라 변화하며 전도중심은 상하단의 산화막 두께에 따라 변화한다. 비대칭 이중게이트 MOSFET는 문턱전압이하 스윙의 저하 등 단채널효과를 감소시키기에 유용한 소자로 알려져 있다. 포아송방정식의 해석학적 해를 이용하여 문턱전압이하 스윙을 유도하였으며 상하단의 산화막 두께 비가 전도중심 및 문턱전압이하 스윙에 미치는 영향을 분석하였다. 문턱전압이하 스윙 및 전도중심은 상하단 게이트 산화막 두께 비에 따라 큰 변화를 나타냈다. 특히 하단 게이트 전압은 문턱전압이하 스윙에 큰 영향을 미치며 하단게이트 전압이 0.7V 일 때 $0<t_{ox2}/t_{ox1}<5$의 범위에서 문턱전압이하 스윙이 약 200 mV/dec 정도 변화하는 것을 알 수 있었다.

SRM의 최대 도통비를 갖는 여자전압 제어기법 (Excitation Voltage Control with a maximum Conduction Ratio of SRM)

  • 이상훈;박성준;안진우;김철우
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 2001년도 하계학술대회 논문집 B
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    • pp.977-979
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    • 2001
  • The application of SRM(Switched Reluctance Motor) is dramatically increasing due to a simple mechanical structure, high efficiency and a good high speed characteristics. Generally, turn-off angle of power switch must be limited the demagnetization period. To control high conduction ratio in motor operation and regenerative voltage in the generator operation in the SRM, multi-level voltage control is effective. This paper proposes multi-level inverter to have a maximum conduction ratio of SRM. The proposed method is verified by experiment.

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비대칭 이중게이트 MOSFET의 상하단 산화막 두께비에 따른 전도중심에 대한 문턱전압 의존성 (Conduction Path Dependent Threshold Voltage for the Ratio of Top and Bottom Oxide Thickness of Asymmetric Double Gate MOSFET)

  • 정학기
    • 한국정보통신학회논문지
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    • 제18권11호
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    • pp.2709-2714
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    • 2014
  • 본 연구에서는 비대칭 이중게이트 MOSFET의 상하단 게이트 산화막 두께 비에 대한 문턱전압 및 전도중심의 변화에 대하여 분석하고자한다. 비대칭 이중게이트 MOSFET는 상하단 게이트 산화막의 두께를 다르게 제작할 수 있어 문턱전압이하 영역에서 전류를 제어할 수 있는 요소가 증가하는 장점이 있다. 상하단 게이트 산화막 두께 비에 대한 문턱전압 및 전도중심을 분석하기 위하여 포아송방정식을 이용하여 해석학적 전위분포를 구하였다. 이때 전하분포는 가우스분포함수를 이용하였다. 하단게이트 전압, 채널길이, 채널두께, 이온주입범위 및 분포편차를 파라미터로 하여 문턱전압 및 전도중심의 변화를 관찰한 결과, 문턱전압은 상하단 게이트 산화막 두께 비에 따라 큰 변화를 나타냈다. 특히 채널길이 및 채널두께의 절대값보다 비에 따라 문턱전압이 변하였으며 전도중심이 상단 게이트로 이동할 때 문턱전압은 증가하였다. 또한 분포편차보단 이온주입범위에 따라 문턱전압 및 전도중심이 크게 변화하였다.

멀티레벨 인버터를 이용한 SRM의 여자전압제어 (Excitation Voltage Control of SRM with Multi-Level Inverter)

  • 강유정;이상훈;박성준;안진우
    • 전력전자학회:학술대회논문집
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    • 전력전자학회 2001년도 추계학술대회 논문집
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    • pp.29-32
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    • 2001
  • The application of SRM(Switched Reluctance Motor) is dramatically increasing due to a simple mechanical structure, high efficiency and a good high speed characteristics. To control high conduction ratio in motor operation and regenerative voltage in the generator operation multi-level voltage control is effective. This paper proposes multi-level inverter to have a maximum conduction ratio of SRM. The proposed method is verified by experiments.

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제작방법에 따른 전력케이블용 폴리에틸렌 박막의 전기전도특성 (The Electrical Conduction Properties of Polyethylene Thin Film for Power Cable with Manufacturing Methods)

  • 조경순;이용우;이수원;홍진웅
    • E2M - 전기 전자와 첨단 소재
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    • 제10권5호
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    • pp.453-460
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    • 1997
  • In order to investigate the electrical conduction properties of polyethylene thin film for power cable with manufacturing methods, the thickness of specimen was the 30, 100[${\mu}{\textrm}{m}$] of LDPE and 200[${\mu}{\textrm}{m}$] of XLPE were manufactured. The experimental condition for conduction properties was measured until the breakdown occurs at temperature ranges from 30 to 110[$^{\circ}C$] and the electric field from 1$\times$10$^3$to 5$\times$10$^{6}$ [V/cm]. As for increase of temperature, the current density of LDPE was increased with constant ratio in low field, but changes with exponential function in high electric field. The tunnel current of pre-breakdown region is shifted toward low field as much as thermal excitation energy. At low electric field, the XLPE showed dominant electrical conduction properties by thermal excitation, and transformation of the electron was resisted by the crystal at high electric field.

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바이닐피리딘 그라프트 폴리에틸렌의 공간전하 및 전기전도 특성 (Space Charge and Conduction Characteristics of Vinylpyridine Grafted Polyethylene)

  • 오우정;서광석;김종은
    • 한국전기전자재료학회:학술대회논문집
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    • 한국전기전자재료학회 1998년도 추계학술대회 논문집
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    • pp.219-222
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    • 1998
  • The space charge and conduction characteristics of chemically modified vinylpyridine (VP) grafted low density polyethylene (LDPE) was investigated. VP grafted LDPE was analyzed by elemental analysis (EA) to confirm the grafting reaction. Homocharge was developed in VP grafted LDPE at low graft ratios and changed to heterocharge with increasing the content of VP. In conduction experiment, current densities of VP grafted LDPE were lower than that of LDPE and VP grafted LDPEs showed almost the same conduction characteristics as vinylpyridine graft ratio increased

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$O_2/(Ar+O_{2})$비에 따른 바나듐 산화막의 구조적, 전기적 특성 (The Structural and Electrical Properties of Vanadium Oxide Thin Films as $O_2/(Ar+O_{2})$ ratio)

  • 최용남;최복길;최창규;김성진
    • 한국전기전자재료학회:학술대회논문집
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    • 한국전기전자재료학회 2001년도 하계학술대회 논문집
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    • pp.729-732
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    • 2001
  • In this study, the effect of oxygen partial pressure on the electrical properties of vanadium oxide(VO$_{x}$) thin films were investigated. The thin films were prepared by r.f. magnetron sputtering from V$_2$O$_{5}$ target in a gas mixture of argon and oxygen. The oxygen partial pressure ratio is changed from 0% to 8%. I-V characteristics were distinguished between linear and nonlinear region. In the low field region the conduction is due to Schottky emission, while at high fields it changes to Fowler-Nordheim tunneling type conduction. The conductivity measurements have shown an Arrhenius dependence of the conductivity on the temperature.ure.

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XLPE 절연케이블내 금속성 불순물이 절연파괴에 미치는 영향 (Effects of Dielectric Breakdown in XLPE Insulation Cables by Metal Impurities)

  • 이우선;최창주;정용호;김남오;김정구;김상준
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 1997년도 하계학술대회 논문집 C
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    • pp.1196-1198
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    • 1997
  • In this work, simultaneous measurement such as change distribution and electrical conduction of maleic anhydride grafted XLPE was investigated. Heterocharge was found in XLPE and it decreased with increasing MAR graft ratio in XLPE-g-MAH. Conduction currents also decreased with increasing MAR graft ratio. The relationship between the space change behavior and the electrical conduction characteristics in XLPE-g-MAH is discussed.

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일축연신에 따른 Polyphenylene Sulfide(PPS)의 전기전도 및 광전도 특성 (The Properties of Electrical Conduction and Photoconduction in polyphenylene Sulfide(PPS) by Uniaxal Elongation)

  • 이운용;장동욱;신태수;임기조;류부형
    • 한국전기전자재료학회논문지
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    • 제11권10호
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    • pp.763-767
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    • 1998
  • In this paper, it is investigated how the morphology and electrical properties in Polyphenylene Sulfide(PPS) changed by uniaxial elongation. XRD(X-ray diffraction) pattern shows that interplanar distance and crystallinities are decreased by increasing elongation ratio. electrical conduction mechanism of PPS is explained as Schottky emission mechanism. the electrical current is decreased by increasing elongation ratio. The conductivity is changed considerably above the glass transition temperature around 82(>$^{\circ}C$). The band gap of PPS is evaluated as 3.7~4(eV)

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