• 제목/요약/키워드: Cold electron emission

검색결과 29건 처리시간 0.021초

전자빔 인출을 위한 2차전자방출 특성 연구 (Characteristics of Secondary Electron Emission for Electron Beam Extraction)

  • 우성훈;이홍식;이광식
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 2003년도 추계학술대회 논문집 전기물성,응용부문
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    • pp.204-206
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    • 2003
  • Electron beam generator of cold cathode type has been developed for industrial application, for example, waste water cleaning, flue gas cleaning, and pasteurization etc. The operational principle is based on the emission of secondary electrons from cold cathode when ions in the plasma hit the cathode, which are accelerated toward exit window by the gradient of an electric potential. The characteristics of secondary electron emission are studied by comparing total cathode current with ion current.

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몰리브덴 팁 전계 방출 소자를 이용한 CRT의 냉음극 전자총의 제조 및 특성 평가 (Fabrication and Characterization of Cold Cathode Electron-gun of CRT using Mo-tip Field Emitter Array)

  • 주병권;김훈;서상원;박종원;이윤희;김남수
    • 대한전기학회논문지:전기물성ㆍ응용부문C
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    • 제50권8호
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    • pp.409-413
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    • 2001
  • In the electron-gun of CRT, the Mo-tip FEA was employed as cold cathode in order to replace the conventional thermal cathode. The Mo-tip FEA was designed and fabricated according to CRT specification and mounted on the electron-gun. It was known that fabricated cold cathode electron-gun showed better performance in terms of maximum emission current and switch-on time when compared with the ones of thermal cathode electron-gun, but some geometrical structures in the inside of electron-gun must be changed to reduce the gate leakage current. Finally, the potential applicability was guaranteed by means of operating the 19 inch-sized LG-color CRT using the fabricated cold cathode electron-gun.

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Switch-on Phenomena and Field Emission from Multi-Walled Carbon Nanotubes Embedded in Glass

  • Bani Ali, Emad S;Mousa, Marwan S
    • Applied Microscopy
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    • 제46권4호
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    • pp.244-252
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    • 2016
  • This paper describes a new design of carbon nanotube tip. $Nanocly^{TM}$ NC 7000 Thin Multiwall Carbon Nanotubes of carbon purity (90%) and average diameter tube 9.5 nm with a high aspect-ratio (>150) were used. These tips were manufactured by employing a drawing technique using a glass puller. The glass microemitters with internal carbon nanotubes show a switch-on effect to a high current level (1 to $20{\mu}A$). A field electron microscope with a tip (cathode)-screen (anode) separation at ~10 mm was used to characterize the electron emitters. The system was evacuated down to a base pressure of ${\sim}10^{-9}$ mbar when baked at up to ${\sim}200^{\circ}C$ overnight. This allowed measurements of typical Field Electron Emission characteristics; namely the current-voltage (I-V) characteristics and the emission images on a conductive phosphorus screen (the anode). Fowler-Nordheim plots of the current-voltage characteristics show current switch-on for each of these emitters.

원추형 기판 위에 탄소 나노튜브의 선택적 성장이 전계방출 특성에 미치는 영향 (Effects of Selective Growth on Electron-emission Properties of Conical-type Carbon Nanotube Field-emitters)

  • 김부종;노영록;박진석
    • 반도체디스플레이기술학회지
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    • 제11권1호
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    • pp.61-65
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    • 2012
  • In this study, for use of carbon nanotubes (CNTs) as a cold cathode of x-ray tubes, we examine the effects of selective growth of CNTs on their field emission properties and long-term stability. The selective growth of CNTs was performed by selectively etching the catalyst layer which was used for CNTs' nucleation. CNTs were grown on conical-type tungsten substrates using an inductively-coupled plasma chemical vapor deposition system. For all the grown CNTs, their morphologies and microstructures were analyzed by field-emission scanning electron microscope and Raman spectroscopy. The electron-emission properties of CNTs and the long-term stability of emission currents were measured and characterized according to the CNTs' growth position on the substrate.

냉음극형 대면적 펄스 전자빔 가속기의 빔인출 특성 (Characteristics of Electron Beam Extraction in Cold Cathode Type Large Cross-Sectional Pulsed Electron Beam Generator)

  • 우성훈;이광식;이동인;이홍식
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 2001년도 하계학술대회 논문집 C
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    • pp.1609-1611
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    • 2001
  • A large cross-section pulsed electron beam generator of cold cathode type has been developed for industrial applications, for example, waste water cleaning, flue gas cleaning, and pasteurization etc. The operational principle is based on the emission of secondary electrons from cold cathode when ions in the plasma hit the cathode, which are accelerated toward exit window by the gradient of an electric potential. The conventional electron beam generators need an electron scanning beam because the small cross section thermal electron emitter is used. The electron beam of large cross-section pulsed electron beam generator do not need to be scanned over target material because the beam cross section is large by 300$cm^2$. We have fabricated the large cross-sectional pulsed electron beam generator with the peak energy of 200keV and beam diameter of 200mm and obtained the large area electron beam in the air. The electron beam current has been investigated as a function of accelerating voltage, glow discharge current, helium pressure, distance from the exit window and radial distribution in front of the exit window.

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냉음극형 대면적 전자빔의 공간적 분포 특성 (Characteristics of spatial distribution of cold cathode type large aperture electron beam)

  • 우성훈;;조주현;김광훈;이홍식;임근희;이광식
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 1999년도 하계학술대회 논문집 E
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    • pp.2170-2172
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    • 1999
  • A low energy large aperture(LELA) pulsed electron beam generator of a cold cathode type has been developed for environmental applications, for example, waste water cleaning, flue gas cleaning, and pasteurization etc. The operational principle is based on the emission of secondary electrons from cold cathode when ions in the plasma hit the cathode, which are accelerated toward exit window by the gradient of an electric potential. We have fabricated the LELA electron beam generator with the peak energy of 200keV and beam diameter of 200mm and obtained the large aperture electron beam in air. The electron beam current density has been investigated as a function of glow discharge current, accelerating voltage and radial distribution in front of the exit window foil. The plasma density and electron temperature have been measured in order to confirm the relation with the electron beam current density. We are going to upgrade the LELA electron beam generator in the electron energy, electron beam current and stability of operation for various applications.

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Carbon nanotubes for Field Emission Displays.

  • Milne, W.I.
    • 한국정보디스플레이학회:학술대회논문집
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    • 한국정보디스플레이학회 2004년도 Asia Display / IMID 04
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    • pp.919-922
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    • 2004
  • The Field Emission Display is potentially an excellent display with high brightness and low power consumption with wide viewing angle but more work is still needed in order to identify the ideal electron emitter for such displays. This paper will review the work that we have carried out in Cambridge aver the past couple of years on optimisation of Carbon nanotubes for use as the cold cathode emitters that are possible candidates as the electron sources in second generation FEDs.

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산화공정에 따른 Porous Poly-Silicon Emitter의 방출특성 조사 (Electron Emission Characteristic of Porous Poly-Silicon Emitter as a Oxidation process)

  • 제병길;배성찬;최시영
    • 대한전자공학회:학술대회논문집
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    • 대한전자공학회 2003년도 하계종합학술대회 논문집 II
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    • pp.722-726
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    • 2003
  • 본 논문에서는 Porous poly-silicon cold cathode에 의해 전자를 방출하는 Ballistic electron surface-emitting display(BSD)의 전계방출 특성을 실험했다. BSD는 nanocrystalline을 둘러싼 산화막을 multi-tunneling한 전자에 의해 발광이 되는 mechanism이기 때문에 산화막의 두께를 변수로 두어 특성을 실험했다. 900℃에서 1시간에서 3시간까지 30분 간격으로산화 반응을 진행하였으며, leakage current와 emission current의 비로 효율을 나타내었을 때 1시간 30분 동안 산화 반응을 한 시료가 가장 좋은 특성을 나타내었다.

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Switch-on Phenomena and Field Emission from Single-Walled Carbon Nanotubes Embedded in Glass

  • Daradkeh, Samer I.;Mousa, Marwan S.
    • Applied Microscopy
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    • 제47권3호
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    • pp.86-94
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    • 2017
  • In this study, we will describe a new design of carbon nanotubes tip. Single-walled carbon nanotubes produced using high-pressure CO over Fe particles (HiPCO) at CNI, Houston, TX used in this study. These tips were manufactured by employing a drawing technique using glass puller. Field electron microscopies with tips (cathode) to screen (Anode) separation of ~10 mm was used to characterize the electron emitters. The system was evacuated down to base pressure of (${\sim}10^{-8}$ mbar) when baked at up to (${\sim}200^{\circ}C$) over night. An electron field emission patterns, as well as current versus voltage characteristics and Fowler-Nordheim plots, are discussed.

Novel room temperature grown carbon based cathodes for field emission using diamond nano-particle seeding technique

  • Satyanarayana, B.S.;Hiraki, A.
    • 한국표면공학회지
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    • 제34권5호
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    • pp.448-454
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    • 2001
  • Low field electron emission from novel carbon based cold cathodes is reported. The cathodes consisted of a layer of nanoseeded diamond and an over layer of nanocluster carbon films. The nanoseeded diamond was first coated on to thesubstrate. The nanocluster carbon films were then deposited on the nanocrystalline diamond coated substrates using the cathodic arc process at room temperature. The heterostructured microcathodes were observed to exhibit electron emission currents of 1 $\mu$A/cm$^2$ at fields as low as 1.5 to 2V/$\mu$m. The effect of the nanoseeded diamond size and concentration and the properties of different nanocluster carbon films on emission characteristics is presented.

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