• 제목/요약/키워드: Electric field density

검색결과 582건 처리시간 0.028초

정공 수송 재료인 TPD의 전기 전도 특성

  • 김원종;최현민;이종용;최광진;홍진웅
    • 한국전기전자재료학회:학술대회논문집
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    • 한국전기전자재료학회 2009년도 추계학술대회 논문집
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    • pp.170-170
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    • 2009
  • From the analysis of current density-luminance-voltage characteristics of the double layered device in ITO/N,N'-diphenyl-N-N'bis(3-methylphenyl)-1,1'biphenyl-4,4'-diamine(TPD)/tris(8-hydroxyquinoline)aluminum($Alq_3$)/Al, we divided the conductive mechanism by four region according to applied voltage. We have obtained a coefficient of ${\beta}_{ST}$ in schottky region (I) is $4.14{\times}10^{-24}$ at the electric field of $3.2{\times}10^5$ V/cm, a slope in negative resistance region (II) appears negative properties decreasing the current density J for proportional in -1.58 square at a electric field of $7.3{\times}10^5$ V/cm. A coefficient of ${\beta}_{PF}$ in Poole-Frenkel region (III) is $8.28{\times}10^{-24}$ at the electric field of $8.4{\times}10^5$ V/cm, it was confirm어 that ${\beta}_{PF}$ is agrees with a value that relates with ${\beta}_{ST}$ such as ${\beta}_{PF}=2{\beta}_{ST}$ as the ${\beta}_{PF}$ and 2 ${\beta}_{ST}$ satisfied a theoretical prediction. And it was obtained a potential barrier of ${\Phi}_{FN}$ in Fower-Nordheim region(IV) is 0.3 eV at the electric field of $11.2{\times}10^5$ V/cm.

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얇은 산화막의 wear out에 관한 광 조사 효과 (The effect of irradiation on the wear out of thin oxide film)

  • 김재호;최복길;성영권
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 1989년도 추계학술대회 논문집 학회본부
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    • pp.114-118
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    • 1989
  • Due to the increased integration density of VLSI circuits a highly reliable thin oxide film is required to fabricate a small geometry MOS device. The behavior of thermal $SiO_2$ under high electric field and current condition has a major effect on MOS device degration and also the practical use of MOS device under irradiation has cause the degration of thin oxide films. In this paper, in order to evaluate the reliability of thin oxides with no stress applied and stressed by the irradiation under low electric field, the tests of TDDB (Time-dependent-dielectric breakdown) are used. Failure times against electric field are examined and acceleration factor is obtained for each case. Based on the experimental data, breakdown wear out limitation for thin oxide films is characterised.

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Electric Field Effect on Nanochannel Formation in Electrochemical Porous Structures of Alumina

  • Kim, Keun-Joo;Choi, Jae-Ho;Lee, Jung-Tack
    • Transactions on Electrical and Electronic Materials
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    • 제11권5호
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    • pp.230-233
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    • 2010
  • The authors investigated the anodization mechanism of aluminum in an oxalic acid solution, and the electrochemical reaction is very unique for pore formation via the dissolution process, which is very dependent on the surface geometry in nanoporous alumina templates. The cross-sectional nanochannels showed that the geometrical curvature of the initial surface can cause the branching of nanochannels to be adjusted in volume occupancy to be direct to the electric field normal to the surface. The nanoporous alumina with the crystalline $\gamma-Al_2O_3$ phase showed hexagonal ordering at a voltage of 40 V, with a nanohole distance of 102 nm from the charge density oscillation of the oxalic acid solution.

Electroflocking을 이용한 단섬유 프리프레그 제조에 관한 연구 (Manufacture of Short Fiber Prepreg using Electroflocking)

  • 임순호;이상수;박민;김준경;최철림;권성진
    • 한국복합재료학회:학술대회논문집
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    • 한국복합재료학회 2002년도 추계학술발표대회 논문집
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    • pp.288-291
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    • 2002
  • The carbon fiber or glass fiber reinforced prepregs were manufactured using electrostatic flocking technology. The powder of high density polyethylene was used as a matrix. The base film of polyethylene was prepared using a fluidized bed of polyethylene powder under the high electric field. We obtained HDPE film with uniform thickness of minimum $80\mu\textrm{m}$. And the fibers were aligned on the molten HDPE film by the electroflocking process. The short fibers with 1mm were easily electrically charged and aligned under the high electric field. The carbon fibers with high conductivity were elasily electrically charged than the glass fibers with low conductivity. So lower electric field was needed for the carbon fibers.

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ER유체를 작동유체로 하는 클러치의 제작 및 성능 실험 (Design and Performance Test of the ER Fluid Clutch)

  • 장성철;박창수;이종두
    • 한국기계가공학회지
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    • 제3권1호
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    • pp.84-89
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    • 2004
  • This study is a basic one for application of ER Fluid to fluid power systems. By mixing silicone oil with zeolite particles, four kinds of ER fluids were made, in which the weight ratio of zeolite particles are different. We examined how the Yield shear stress and Bingham characteristics of the ER fluids are effected by varying electric field intensity. We designed and constructed a disk type power transmission clutch in which ER fluid fills and this ER fluid transmits the power of drive shaft to the driven shaft. With this equipment, the revolution transmission ratio from the chive shaft to the driven shaft by varying electric field density of the ER fluid was examined.

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전기적 스위칭이 가능한 고분자 분산형 액정 제작 및 동적 홀로그램 기록 특성 (Electrically controllable polymer-dispersed liquid crystal)

  • 성기영;경천수;이영락;최병철;곽종훈;최옥식;이윤우
    • 한국광학회지
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    • 제10권6호
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    • pp.494-499
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    • 1999
  • 전기적으로 굴절율 변조값을 조절할 수 있는 부피형 홀로그램 매질(HPDLC)을 제작하였다. HPDLC는 4가 acrylate monomer를 기초로 한 전폴리머(prepolymer)와 액정 혼합물 E7 등으로 구성되어져 있다. 제작된 매질의 광학적 특성을 조사하기 위해 액정 농도, 전기장의 세기에 따른 회전효율을 측정하고, 홀로그래피 방법으로 상을 기록한 후 재생된 상을 전기적으로 조절할 수 있음을 보였다.

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GIS 모선부 절연설계/평가 프로그림 개발 (The Development of Program for Insulation Design/Evaluation of GIS Bus Section)

  • 김동현;석복렬;김영기;이형구;강종호;조만규
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 2003년도 하계학술대회 논문집 B
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    • pp.1060-1062
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    • 2003
  • In this study, an insulation design program which can calculate electric field of the GIS bus parts easily was developed. It also can evaluate the insulation safety depending on gas density. For bus parts of $1{\varphi}$ GIS, it was intended to provide a optimal diameter of a conductor and an enclosure automatically for the convenience of GIS insulation designer. This program was coded by Visual Basic and electric field was calculated by the Charge Simulation Method(CSM), which is one of the most accurate method for an electric field analysis.

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HDPE/EVA혼합수지의 공간 전하 분포에 관한 연구 (A Study on Space Charge Distribution of HDPE Mixed with EVA)

  • 정의환;허준;윤재훈;임기조;이흥규
    • 전기학회논문지
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    • 제58권11호
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    • pp.2229-2235
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    • 2009
  • In this paper, each specimen blended at weight proportions of 80% HDPE to 20% EVA, 70% HDPE to 30% EVA, 60% HDPE to 40% EVA, and 50% HDPE to 50% EVA was manufactured respectively. The insulation performances of the proposed insulator were compared with conventional XLPE, main insulating material of CV cable on the basis of the investigation results of DC insulation performances. From the space charge density, electric field and potential profiles with raising DC voltage and time variation in HE82, distortion of electric field distribution was improved. As EVA mixed into the bulks acts as nucleation in crystallization process of HDPE, the size of spherulites became decreased and finally formed continuous network structure. Ultimately, it resulted from extinction of space charge in the interfacial region of spherulites.

X-ray scattering study on the electric field-induced interfacial magnetic anisotropy modulation at CoFeB / MgO interfaces

  • Song, Kyung Mee;Kim, Dong-Ok;Kim, Jae-Sung;Lee, Dong Ryeol;Choi, Jun Woo
    • Current Applied Physics
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    • 제18권11호
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    • pp.1212-1217
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    • 2018
  • The electric field-induced modifications of magnetic anisotropy in CoFeB/MgO systems are studied using X-ray resonant magnetic scattering and magneto-optical Kerr effect. Voltage dependent changes of the magnetic anisotropy of -12.7 fJ/Vm and -8.32 fJ/Vm are observed for Ta/CoFeB/MgO and Hf/CoFeB/MgO systems, respectively. This implies that the interfacial perpendicular magnetic anisotropy is reduced (enhanced) when electron density is increased (decreased). X-ray resonant magnetic scattering measurements reveal that the small in-plane magnetic component of the remanent state of CoFeB/MgO systems with weak magnetic anisotropy changes depending on the applied voltage leading to modification of the magnetic anisotropy at the CoFeB/MgO interface.

변류기(p-CT)를 적용한 YBCO 초전도 저항형 한류기의 ?치 특성 (Quench Behaviors of Superconducting YBCO film for Fault Current Limiters applying Protective Current Transformer)

  • 박권배;이방욱;강종성;오일성;현옥배
    • Progress in Superconductivity
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    • 제5권2호
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    • pp.128-131
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    • 2004
  • The resistive superconducting fault current limiters (SFCLs) are very attractive devices for the electric power network. But they have some serious problems when the YBCO thin films were used for the current limiting materials due to the in homogeneities caused by manufacturing process. When the YBCO films have some inhomogeneities, simultaneous quenches are difficult to achieve when the fault current limiting units are connected in series for increasing operating voltage ratings. Magnetic field application is one of the prospective way of inducing simultaneous quenches far the series-connected resistive FCL components. Magnetic field was typically generated by the fault current thorough a coil, which is connected to components of the fault current limiter in series, leaving the problem, which provides significant inductance to the power line and suppresses critical current density of the superconducting components. In this article we investigated the possible application of the protective current transformer (p-CT), which is available current source to the magnetic coil. This system inductively coupled to the circuit, therefore, remarkably reducing impedance to the circuit. The current by the protective current transformer was directly fed to the coil, generating magnetic field large enough to reduce critical current density of the components. This successfully induced simultaneous quenches of the series-connected resistive FCL components.

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