• Title/Summary/Keyword: Schottky effect

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

  • 최용남;최복길;최창규;김성진
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 2001.07a
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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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Charge Transport at the Interfaces between Carbon Nanotube and Wetting Metal Leads Mediated via Topological Defects

  • Ko, Kwan Ho;Kim, Han Seul;Kim, Hu Sung;Kim, Yong-Hoon
    • Proceedings of the Korean Vacuum Society Conference
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    • 2014.02a
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    • pp.179.2-179.2
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    • 2014
  • Carbon nanotubes (CNT)-metal contacts play an important role in nanoelectronics applications such as field-effect transistor (FET) devices. Using Al and (10,0) CNT, we have recently showed that the CNT-metal contacts mediated via topological defects within CNT exhibits intrinsically low contact resistance, thanks to the preservation of the sp2 bonding network at the metal-CNT contacts.[1] It is well-established that metals with good wetting property such as Pd consistently yield good contacts to both metallic and semiconducting CNTs. In this work, the electronic and charge transport properties of the interfaces between capped CNT and Pd will be investigated based on first-principles computations and compared with previous results obtained for the Al electrodes.

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The Electrical Conduction Characteristics of Silicone oils due to Viscosity Variation (점도변화에 따른 실리콘유의 전기전도특성)

  • 조경순;홍진웅;신종열;이충호;이수원
    • Electrical & Electronic Materials
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    • v.10 no.9
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    • pp.945-951
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    • 1997
  • Inorder to investigated electrical conduction characteristics of silicone oils due to viscosity variation we studied the electrical conduction properties at temperature range of 10~110[$^{\circ}C$] and electrical field from 1 to 1.33$\times$10$^4$[V/cm] The viscosity of used specimens was low viscous(1, 2, 5[cSt]) silicone oils. It was shown the ohmic conduction characteristics in low temperature and low field by Ion dipole and humidity included specimen. And we known the conduction mechanism due to electron injection by Schottky's effect in the high temperature an d high field region.

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ENHANCEMENT OF PHOTOVOLTAIC PERFORMANCE IN COPPER PHTHALOCYNINE THICK FILM SOLAR CELLS

  • Ruiono, Yo Tomota;Momose, Yoshihiro;Takeuchi, Manabu
    • Journal of Surface Science and Engineering
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    • v.29 no.6
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    • pp.673-677
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    • 1996
  • Copper phthalocyanine(CuPc) thick film solar cells were fabgricated byspin coating and their photovoltaic behavior was studied. Polyvinylidene fluoride (PVdF) was used for the binder. Aluminum and indium were employed as electrode metals to form Schottky contact to CuPc layer. The cells showed rectifying J-V characteristics in the dark and photovoltaic effect associated with white light irradiation. The photovoltaic performance of the cells strongly depended on contact metals, in which the formation of oxide layer between binder layer and electrode interface affected the solar cell. Influnce of the CuPc layer thickness, CuPc/PVdF ratio on the photovoltaic performance of the cells were also examined.

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Effect of electric field on asymmetric degradation in a-IGZO TFTs under positive bias stress (Positive bias stress하에서의 electric field가 a-IGZO TFT의 비대칭 열화에 미치는 영향 분석)

  • Lee, Da-Eun;Jeong, Chan-Yong;Jin, Xiao-Shi;Gwon, Hyeok-In
    • Proceedings of the Korean Institute of Surface Engineering Conference
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    • 2014.11a
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    • pp.108-109
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    • 2014
  • 본 논문에서는 gate와 drain bias stress하에서의 a-IGZO thin-film transistors (TFTs)의 비대칭 열화 메커니즘 분석을 진행하였다. Gate와 drain bias stress하에서의 a-IGZO TFT의 열화 현상은 conduction band edge 근처에 존재하는 oxygen vacancy-related donor-like trap의 발생으로 예상되며, TFT의 channel layer 내에서의 비대칭 열화현상은 source의 metal과 a-IGZO layer간의 contact에 전압이 인가되었을 경우, reverse-biased Schottky diode에 의한 source 쪽에서의 높은 electric field가 trap generation을 가속화시킴으로써 일어나는 것임을 확인할 수 있었다.

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A study on conduction current and D.C. breakdown characteristics in dielectric liquids (절연유의 도전전류와 직류절연파괴특성에 관한 연구)

  • 서국철
    • 전기의세계
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    • v.30 no.4
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    • pp.231-236
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    • 1981
  • It has been known that D.C. breakdown Voltage is lower than A.C. breakdown Voltage in insulatingoil, but there are still many unvivid points at electric conduction in breakdown or under of high electric field. This study measured the electric current-electric field characteristics (I-E characteristics) and the breakdown Voltage under of D.C. electric field of insulating oil using the system of electrodes that are near the Uniform electric field with a result. I can study, electric conduction in area of high electric field depends upon the Schottky effect. The liquidity of breakdown electric field takes place by the local concentration of electric field. The longer gap is and the more electric current is the more breakdown Voltage decreased. There are not almost the change of electric current-electric field characteristics by materials of electrode.

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Current-voltage Characteristics of Ceramics with Positive Temperature Coefficient of Resistance

  • Li, Yong-Gen;Cho, Sung-Gurl
    • Journal of the Korean Ceramic Society
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    • v.40 no.10
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    • pp.921-924
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    • 2003
  • A current-voltage relation for Positive Temperature Coefficient of Resistance (PTCR) ceramic was derived and compared with the experimental data. The new current-voltage relation was developed based on Heywangs double Schottky barrier model and a bias distribution across the grain boundary. The voltage limitation V < 4${\Phi}$$\sub$b/ suggested by Heywang is no longer necessary in the new expression for the voltage dependence of the resistance. The pulsed voltages were applied to the PTCR ceramic specimen in order to avoid possible temperature variation during the measurement.

A study on the growth and characterization of $\alpha$ -Sexithienyl thin films by OMBD(Organic Molecular Beam Deposition) technique (유기 분자빔 성막법을 이용한 $\alpha$-Sexithieny1 박막의 성장 및 특성 연구)

  • 박용인;박주강;권오관;김영관;최종선;신동병;손병청;강도열
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 1996.11a
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    • pp.187-190
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    • 1996
  • Conducting polymers have band structures similar to those of inorganic semiconductors such as silicon. Several electronic devices have been constructed with conjugated polymers, mainly Schottky diodes and Metal-Insulator-Semiconductor Field-Effect Transistors (MISFET's). Organic semiconductor has been reported as active materials in MISFET's.$^{1.4}$ In our laboratory, $\alpha$-Sexithiencyl ($\alpha$-6T) has been synthesized and purified by sublimation method. In this study, thin films of $\alpha$-Sexithienyl were prepared on various substrates in ultra-high vacuum chamber by vacuum evaporation method, so called OMBD(Organic Molocular Beam Deposition).$^{7.9}$ The $\alpha$-Sexithienyl thin films were deposited with various deposition conditions. The crystalline structure, and molecular orientation of these films have being studied by using UV/Vis. spectroscopy and X-Ray Diffractometry.

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Ignition Characteristics Analysis of Pseudospark Discharge using Hybrid Fluid-Particle(Monte Carlo) Method (복합 유체-입자(몬테칼로)법을 이용한 유사스파크 방전의 기동 특성 해석)

  • 주흥진;심재학;강형부
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 1997.11a
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    • pp.270-274
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    • 1997
  • The numerical model that can describe the ignition of the pseudospark discharge using hybrid fluid-particle method has been developed. The evolution process of the discharge has been divided into four phases along the potential distribution. After the plasma enters in the hollow cathode, the confining effect which is one of hollow cathode properties occurs and the electron current on anode rises rapidly. As the plasma expands successively, the sheath contracts and as the electric field in the sheath increases, the field-enhanced thermionic emission(Schottky emission) occurs. From numerical results, the physical mechanism that causes the rapid current rise in the ignition of the pseudospark discharge could be identified.

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The effect of rectifying diodes on the efficiency of Piezoelectric Micro-Power Generator (정류다이오드의 특성이 저전력 압전발전기의 효율에 미치는 영향)

  • Kim, Hye-Joong;Min, Hyn-Jun;Kang, Sung-Muk;Kim, Ho-Seong
    • Proceedings of the KIEE Conference
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    • 2007.07a
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    • pp.1554-1555
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    • 2007
  • 본 논문에서는 기존의 Piezoelectric micropower generator 연구에서 주로 사용되던 Schottky 다이오드 대신 역방향 누설전류가 아주 작은 PAD1과 같은 다이오드를 사용함으로써 기계적 에너지로부터 전기적 에너지로의 에너지 변환효율을 획기적으로 증가시킬 수 있음을 확인하였다. 시뮬레이션을 위해 실험결과를 초기 값으로 한 최적화된 등가회로를 구성하였으며, 실험과 PSPICE 시뮬레이션을 통해 분석한 결과 에너지 변환효율은 최고 100% 이상 증가됨을 알 수 있었다. 특히 미세한 진동으로부터의 매우 작은 기계적 에너지를 이용하는 경우에는 PAD1과 같이 역방향 누설전류가 아주 작은 다이오드를 이용해야만 전기에너지로의 변환이 가능함을 증명하였다.

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