• Title/Summary/Keyword: electron emission

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Numerical Calculation Study on the Generalized Electron Emission Phenomenon

  • Kim, Hee-Tae;Yu, Soon-Jae
    • Journal of Information Display
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    • v.10 no.4
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    • pp.158-163
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    • 2009
  • There are two kinds of well-known electron emissions from metal: field and thermionic emission. For thermionic emission, electrons come out of a metal due to the thermal energy, whereas for field emission, electrons tunnel out of a metal through the strong electric field. In this study, the most general electron emission caused by the temperature and electric field with a free electron gas model was considered. The total current density of electron emission comes from the field emission effect, where the electron energy is lower than vacuum, and from the thermionic-emission effect, where the electron energy is higher than vacuum. The total current density of electron emission is shown as a function of the temperature for a constant electric field, and as a function of the electric field for a constant temperature.

Electron Emission from $Pb(Zr_xTi_{1-x})O_3$ Ferroelectrics by Pulsed Electric Field (펄스 전기장에 의한 $Pb(Zr_xTi_{1-x})O_3$ 강유전체의 전자 방출)

  • 김용태;윤기현;김태희;박경봉;곽상희
    • Journal of the Korean Ceramic Society
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    • v.37 no.1
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    • pp.6-11
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    • 2000
  • Electron emission from the Pb(ZrxTi1-x)O3 ferroelectrics by pulsed electric field has been investigated as a function of Zr/Ti ratios such as 35/65, 50/50 and 65/35 below 250kV/cm. Electrons were emitted regardless of the applied field polarity to the rear electrode. When the negative field was applied to the rear electrode, the electron emission charge was more stable. It was proved that the electrons were emitted at the edge of the upper electrode. The emission charge increased in order of 65/35>50/50>35/65. The electron emission characteristics were dependent on the ferroelectric properties such as polarization and coercive field. The emission charge and emission threshold field were affected by the polarization change and the coercive field, respectively. This result explains that the electron emission is a field emission with polarization induced surface potential by a modified Fowler-Nordheim plot of emission charge.

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Semiconductor Nanowires;Their Emission Stability and Energy Distribution

  • Yu, Se-Gi;Yi, Whi-Kun;Lee, Sang-Hyun;Heo, Jung-Na;Jeong, Tae-Won;Lee, Jeong-Hee;Lee, Soo-Chang;Kim, J.M.;Lee, Cheol-Jin;Lyu, Seung-Chul;Han, Jae-Hee;Yoo, Ji-Beom
    • 한국정보디스플레이학회:학술대회논문집
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    • 2002.08a
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    • pp.1028-1031
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    • 2002
  • Ga-based semiconductor nanowires (GaN, GaP) were synthesized by the reaction of Ga metal and GaN/GaP powder with a $NH_3/Ar$ gas using thermal chemical vapor deposition. The field emission and emission stability under oxygen and argon environments were investigated. Field emission energy distributions of electrons from these nanowires revealed that field emission mechanism of the semiconductor nanowires were different from carbon nanotubes.

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Electron Emission Theory for LCD Backlight

  • Kim, Hee-Tae;Lee, Dong-Chin;Nam, Seok-Hyun;Jang, Tae-Seok
    • 한국정보디스플레이학회:학술대회논문집
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    • 2008.10a
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    • pp.1602-1605
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    • 2008
  • We considered most general electron emission caused by temperature as well as electric field with a free electron gas model. The total electron emission current density comes from field emission effect where electron energy is lower than vacuum and from thermionic emission effect where electron energy is higher than vacuum. The total electron emission current density is shown as a function of temperature for constant electric field, and as a function of electric field for constant temperature.

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Field Emission Current Enhancement in CNTs by Laser Irradiation

  • Jeong, Tae-Won;Yu, Se-Gi;Yi, Whi-Kun;Lee, Chang-Soo;Lee, Jeong-Hee;Heo, Jung-Na;Yoo, Ji-Beom;Kim, Won-Seok;Lee, Y.H.;Kim, J.M.
    • Journal of Information Display
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    • v.2 no.4
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    • pp.23-28
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    • 2001
  • Field emission characteristics of carbon nanotubes(CNTs) on four kinds of metallic substrates have been investigated under the irradiation of a laser. The field emission measurement reveals that after laser irradiation the current was increased and new humps at the field emission current was found. The current enhancement was thought to have occurred due to the fact that the electrical contact between CNTs and metals was improved due to the irradiation of the laser.

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Pulse electric field-excited electron emission from Pb$(Zr_xTi_{1-x})O_3$ ceramics prepared by conventional solid state reaction (고상 반응법에 의해 제조된 Pb$(Zr_xTi_{1-x})O_3$ 세라믹스에서 펄스 전계에 의한 전자 방출)

  • Kwak, Sang-Hee;Kim, Tae-Heui;Park, Kyung-Bong;Kim, Chang-Soo
    • Proceedings of the KIEE Conference
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    • 1999.07d
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    • pp.1867-1869
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    • 1999
  • Pulse electric field induced electron emission from ferroelectrics has been studied with Pb$(Zr_xTi_{1-x})O_3$ ceramics with varying Zr/Ti ratio from 35/65 to 65/35, Electron emission was proved to be concentrated on the electrode edge by emission profile test and emission capture photographs. The 65/35 composition showed largest emission charge in lowest field and lowest emission threshold field. The emission characteristics are closely dependent on their ferroelectric properties in hysteresis curve. Electron emission charge increases with the polarization charge and emission threshold voltage is dependent on coercive field regardless of their composition. But dielectric constant has little relation with emission property. Electron emission charge increases exponentially with pulse electric field irrespective of composition. On the assumption that the surface potential is linear with the pulse electric field, electron emission can be regarded as a field emission at the electrode edge using Fowler-Nordheim plot of ln$(Q_e/E_{fe})$ to $1/E_{fe}$.

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Microchannel plates for field emission displays

  • Sunghwan Jin;Yu, Se-Gi;Jungna Heo;Taewon Jeong;Lee, Junghee;Whikun Yi;Park, Yongsoo;Kim, Jongmin
    • Journal of Korean Vacuum Science & Technology
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    • v.4 no.4
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    • pp.93-96
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    • 2000
  • Microchannel plates (MCPs) have been developed by introducing new materials and process technologies. Main body was made of alumina by programmable punching, laminating, and firing. The channel walls of pore arrays of an MCP were deposited with thin films by electroless copper plating and sol-gel process. Our MCP has advantages such as easy fabrication, durability, high temperature endurance, and applicability to the large size comparing with the conventional MCPs. Experiments on the brightness of an MCP incorporated FED revealed that the FED with a MCP is three to four times brighter than a conventional FED. Moreover, the focusing in a FED is improved. Incorporating an MCP into a FED is one of promising methods to enhance the characteristics of the FED. In addition, amplification yield of the MCP is measured for varying the aspect ratio and the input current.

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Measurement of Secondary Electron Emission Coefficient on Deposition Time of the Silicon Thin Films (실리콘박막의 증착시간에 따른 감마계수 측정법 개발)

  • Lee, Jung-Hui;Choi, Byoung-Jung;Yang, Sung-Chae
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 2006.11a
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    • pp.330-331
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    • 2006
  • Recently, plasma display panels (PDPs) are highlighted for the flat type display device. Therefore, much attention has been paid to secondary electron emission coefficient of the electrode protective material of PDPs. As PDPs is developing, the concern about secondary electron emission coefficient ($\gamma$) which is related with PDPs electrode protection material is increasing continually. So the concern about the way to how to measure secondary electron emission coefficient is on the rise. At present, the way to how to measure secondary electron emission coefficient is developed by some research groups, which is giving some research part's advance help. In this research, we have studied how to measure secondary electron emission coefficient which is related with various thin films more conveniently than previous measurement method. We studied the method of measurement of secondary electron emission coefficient (${\gamma}$) of amorphous silicon films by using Paschen's curve.

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A Study on Emission Characteristics of Ne Gas Using a Single Langmuir Probe Method in Radio-Frequency Inductively Coupled Plasma (13.56MHz ICP에서 단일 탐침법에 의한 Ne 가스의 발광특성 연구)

  • Jo, Ju-Ung;Choi, Yong-Sung;Kim, Yong-Kab;Park, Dae-Hee
    • Proceedings of the KIEE Conference
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    • 2004.11a
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    • pp.150-152
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    • 2004
  • In recent, there have been several developments in lamp technology that promise savings in electrical power consumption and improved quality of the lighting space. The electrodeless fluorescent lamp is intended as a high efficacy replacement for the incandescent reflector lamp in many applications. In this paper, electron temperature and electron density were measured in a radio-frequency inductively coupled plasma using a Langmuir probe method for emission characteristics. Measurement was conducted in an Ne discharge for pressure from 10 [mTorr] and input RF power 100 [W] to 150 [W]. As for the electron density, a electron temperature was more distinguished for a emission characteristic. The results of ideal may contribute to systematic understanding of a electrodeless fluorescent lamps of emission characteristics.

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A Study on Emission Characteristics of Ar, Ne Gas Using a Single Langmuir Probe Method in Radio-Frequency Inductively Coupled Plasma (13.56MHz ICP에서 단일 탐침법에 의한 Ar, Ne 가스의 발광특성 연구)

  • Jo, Ju-Ung;Choi, Yong-Sung;Kim, Yong-Kab;Park, Dae-Hee
    • Proceedings of the KIEE Conference
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    • 2004.11a
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    • pp.167-170
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    • 2004
  • In recent, there have been several developments in lamp technology that promise savings in electrical power consumption and improved quality of the lighting space. The electrodeless fluorescent lamp is intended as a high efficacy replacement for the incandescent reflector lamp in many applications. In this paper, electron temperature and electron density were measured in a radio-frequency inductively coupled plasma using a Langmuir probe method for emission characteristics. Measurement was conducted in an Argon, Ne discharge for pressure from 1 [mTorr] and input RF power 10 [W] to 150 [W]. As for the electron density, a electron temperature was more distinguished for a emission characteristic. The results of ideal may contribute to systematic understanding of a electrodeless fluorescent lamps of emission characteristics.

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