• 제목/요약/키워드: Electrical resistance change

검색결과 503건 처리시간 0.029초

온도에 따른 유기발광소자의 임피던스 분석 (Impedance spectrosocpy depending on temperature in Organic Light-Emitting Diodes)

  • 안준호;정동회;장경욱;송민종;이성일;이준웅;김태완
    • 한국전기전자재료학회:학술대회논문집
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    • 한국전기전자재료학회 2004년도 추계학술대회 논문집 Vol.17
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    • pp.543-546
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    • 2004
  • Bias and frequency-dependent impedance is a technique for the investigation of complex conductivity. At low frequency, complex impedance is dominated by resistive component, and at high frequency by capacitive component. We are going to present the results of the bias and frequency-dependent complex impedance in the device structure of $ITO/Alq_3/Al$ in the temperature range between 10K and 300k. And we will show to change radius of Cole-Cole plot. It will be decrease resistance by temperature. Also equivalent electrical circuit and dielectric relaxation can be accomplished by using the complex impedance analysis.

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자계벡터 가속법에 의한 유도형 서보전동기의 전력회생 구동 (The Regenerative Drive of Induction Servo Motor by the Flux Acceleration Method)

  • 홍순일;홍정표;정승환
    • 융합신호처리학회 학술대회논문집
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    • 한국신호처리시스템학회 2006년도 하계 학술대회 논문집
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    • pp.77-80
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    • 2006
  • This paper based on spiral vector, three phase induction motor is described a detailed modeling by a phase segment methode. Based on this model, A torque control and the equation of regenerative power for the induction motor drive, based on the field acceleration method(FAM), is presented. The speed control system is designed to be applied voltage source inverters that is easy the current type feedback of power regeneration for motor drive. The ability of shaving power to be measured power regeneration has been investigated in speed acceleration and reduction. And it is change of stator resistance that the voltage commands include error, the ripple of exited voltage and torque occur from the results. The experimental tests verify the performance of the proposed regenerative drive for FAM, proving that good behavior of the drive is achieved in the transient and steady-state operating conditions.

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전력설비용 Polyimide의 전압-전류특성 (Voltage-Current Properties of Polyimide use Electrical Power Installation)

  • 전동규;이경섭
    • 한국조명전기설비학회:학술대회논문집
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    • 한국조명전기설비학회 1998년도 학술발표회논문집
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    • pp.112-115
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    • 1998
  • We investigate the qualities of organic materials by which can manufacture organic thin films for solar cells and make thin films for insulation layers of an insulated cable. We give pressure stimulation into organic thin films and detect the induced displacement current. In processing of a device manufacture, We can see the process is good from the change of a surface pressure for organic thin films and transfer ratio of area per molecule. The structure of manufactured device is Au/organic thin films(polyimide)/Au and I-V characteristic of the device is measured from 0[V] to +5[V]. The maximum value of measured current is increased as the number of accumulated layers are decreased. The resistance for the number of accumulated layers, the energy density for an input voltage show desired results, and the insulation of a thin film is better as the interval between electrodes is larger.

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크롬질화박막형 스트레인 게이지의 열처리 특성 (The Annealing Characteristics of Chromiun Nitride Thin-Film Strain Gauges)

  • 서정환;박정도;김인규;정귀상
    • 한국전기전자재료학회:학술대회논문집
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    • 한국전기전자재료학회 1999년도 춘계학술대회 논문집
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    • pp.692-695
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    • 1999
  • This paper presents annealing characteristics of CrN thin-film strain gauges, which were deposited on glass by DC reactive magnetron sputtering in an argon-nitrogen atmosphere)Ar-(5-~25%)$N_2$. The physical and electrical characteristics of these films investigated with the thickness range 3500$\AA$ of CrN thin films, annealing temperature (100~30$0^{\circ}C$) and annealing time (24-72hr) . The optimized condition of CrN thin-film strain gauges were thickness range of 3500$\AA$ and annealing condition(30$0^{\circ}C$ , 48hr) in Ar-10%$N_2$ deposition atmosphere. Under optimum conditions, the CrN thin-films for strain gauge is obtained a high resistivity, $\rho$=1147.65$\Omega$cm a low temperature coefficient of 11.17. And change in resistance after annealing for the CrN thin film were quitely linear and stable.

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플라즈마 표면처리에 따른 고분자절연재료용 유리섬유의 표면개질 (Surface Modification of Glass Fiber for Polymer Insulator by Plasma Surface Treatment)

  • 임경범;이덕출
    • 대한전기학회논문지:시스템및제어부문D
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    • 제52권5호
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    • pp.206-206
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    • 2003
  • It is hard to expect excellent electrical, mechanical and chemical properties from most of the composite materials presently used as insulators due to insufficient wettability property caused by the difference of interfacial properties between the matrix material and the reinforcer. Therefore, various interfacial coupling agents have been developed to improve the interfacial properties of composite materials. But if the wettable coupling agents are used outdoor for a long time, change in quality takes place in the coupling agents themselves, bringing about deterioration of the properties of the composite materials. In this study, glass surface was treated by plasma to examine the effect of dry interface treatment without coupling agent. It was identified that the optimum parameters for the best wettability of the samples at the time of generation of plasma were oxygen atmosphere, 0.1 torr of system pressure, 100 W of discharge power, and 3 minutes of discharge time. Also, the surface resistance rate and dielectric property were improved.

플라즈마 표면처리에 따른 고분자절연재료용 유리섬유의 표면개질 (Surface Modification of Glass Fiber for Polymer Insulator by Plasma Surface Treatment)

  • 임경범;이덕출
    • 대한전기학회논문지:전기물성ㆍ응용부문C
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    • 제52권5호
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    • pp.206-212
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    • 2003
  • It is hard to expect excellent electrical, mechanical and chemical properties from most of the composite materials presently used as insulators due to insufficient wettability property caused by the difference of interfacial properties between the matrix material and the reinforcer. Therefore, various interfacial coupling agents have been developed to improve the interfacial properties of composite materials. But if the wettable coupling agents are used outdoor for a long time, change in quality takes place in the coupling agents themselves, bringing about deterioration of the properties of the composite materials. In this study, glass surface was treated by plasma to examine the effect of dry interface treatment without coupling agent. It was identified that the optimum parameters for the best wettability of the samples at the time of generation of plasma were oxygen atmosphere, 0.1 torr of system pressure, 100 W of discharge power, and 3 minutes of discharge time. Also, the surface resistance rate and dielectric property were improved.

Xe EEFL의 혼합가스에 따른 전기 광학적 특성 (Electrical and Optical properties of Xe EEFL by mixed gas)

  • 김남군;이성진;양종경;박대희
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 2007년도 제38회 하계학술대회
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    • pp.1568-1569
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    • 2007
  • TFT-LCD used in display area is not a light-emissive device itself but TFT-LCD can overcome through the employ of the backlight unit (BLU). BLU is very important device in TFT-LCD system. However, the old-fashion BLU of CCFL type is crucible to the health due to the contained material, mercury (Hg). Moreover, strong temperature dependency of lamp employed with Hg becomes the other disadvantage in practical usage. To solve these problems, Hg-Free lamp with strong thermal resistance property is required to displace the Hg lamp. We studied optical and electrical properties of Xe-Ne-He mixed gas that is dependent on change of mixed ratio and pressure. In our results, the designed lamp without the phosphorescent material has the lowest firing voltage at xe 50%(Ne:He=9:1).

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건조 상태에 따른 CNT 및 ITO로 코팅된 PET 투명전극의 표면 조절 및 내구성 평가 (Surface control and durability evaluation of CNT and ITO coated PET transparent electrode with different dry conditions)

  • 권동준;왕작가;구가영;박종만
    • Composites Research
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    • 제24권5호
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    • pp.17-22
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    • 2011
  • 최근 투명전극으로 주로 사용되고 있는 ITO 재료를 대체하가 위해 CNT를 이용한 투명전극의 활용 연구가 활발히 진행되고 있다. 본 연구에서는 건조온도에 따라 CNT와 ITO의 응집이 일어나는 정도가 달라진다는 점을 이용하여 표면을 조절하여 CNT 및 ITO가 코팅된 폴리에틸렌 테레프탈레이트 (PET)를 제조하였다. CNT를 ITO를 대신할 투명전극으로의 활용 가능성을 평가하면서, 표면의 물성 변화를 유도 하기 위해 코팅 후 건조온도를 $20^{\circ}C$, $80^{\circ}C$, 그리고 $120^{\circ}C$ 3단계로 나누어 표면을 관찰하였다. 전기저항측정법을 활용하여 재료의 내구성 및 전기적 물성을 평가함으로써 제조한 투명전극의 특성을 평가하였다. 전자현미경을 이용하여 건조온도에 따른 표면 변화를 관찰하였고, UV-스펙트럼을 통해 건조온도가 증가함에 따라 투과도가 변화하는 것을 확인하였다. 나노입자의 코팅 표면 조절에 따른 전기적 물성 변화를 확인하기 위해 순환전압전류법을 이용 하였다. CNT 코팅 표면의 내구성이 ITO 코팅 표면의 내구성보다 우수함을 알았다. 그리고, 건조온도가 높을수록 나노입자들의 응집이 크게 증가 하여 내구성이 우수한 코팅 표면을 만들며, 이에 따른 전기적 물성의 향상도 확인하였다.

Zigbee시스템에 적용 가능한 Gain-Variable LNA 설계 연구 (A study on the Design of Gain Variable Low Noise amplifier for Zigbee System)

  • 최혁재;고재형;최진규;김군태;박준홍;윤선우;김형석
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 2009년도 제40회 하계학술대회
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    • pp.1597_1598
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    • 2009
  • In this paper, the techniques and design focus of flexible gain coltrol of LAN(Low Noise Amplifier) using the TSMC 0.18um CMOS process. The design frequency set up a standard on 2.4GHz that is used in Zigbee system. The design concepts a basic Cascode LNA techniques and a swiching circuit consisted of 4 NMOS of load resistance, which convert the output impedenceby tuning on or off. The result show the gain change by NMOS operated swich. The simulation result is that Gain is 10.23~12.96dB and NF(Noise Figure) is 1.41~1.47dB.

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비정질-결정질 가역적 상변환 소자용 Ge8Sb2Te11 박막의 W 도핑에 따른 상변환 특성 평가 (Evaluation on the Phase-Change Properties in W-doped Ge8Sb2Te11 Thin Films for Amorphous-to-Crystalline Reversible Phase-Change Device)

  • 박철진;여종빈;공헌;이현용
    • 한국전기전자재료학회논문지
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    • 제30권3호
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    • pp.133-138
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    • 2017
  • We evaluated the structural, electrical and optical properties of tungsten (W)-doped $Ge_8Sb_2Te_{11}$ thin films. In a previous work, GeSbTe alloys were doped with different materials in an attempt to improve thermal stability. 200 mm thick $Ge_8Sb_2Te_{11}$ and W-doped $Ge_8Sb_2Te_{11}$ films were deposited on p-type Si (100) and glass substrates using a magnetron co-sputtering system at room temperature. The fabricated films were annealed in a furnace in the $0{\sim}400^{\circ}C$ temperature range. The structural properties were analyzed using X-ray diffraction (X'pert PRO, Phillips). The results showed increased crystallization temperature ($T_c$) leading to thermal stability in the amorphous state. The optical properties were analyzed using an UV-Vis-IR spectrophotometer (Shimadzu, U-3501, range : 300~3,000 nm). The results showed an increase in the crystalline material optical energy band gap ($E_{op}$) and an increase in the $E_{op}$ difference (${\Delta}E_{op}$). This is a good effect to reduce memory device noise. The electrical properties were analyzed using a 4-point probe (CNT-series). This showed increased sheet resistance ($R_s$), which reduces programming current in the memory device.