• 제목/요약/키워드: Electric field emission

검색결과 238건 처리시간 0.036초

Electron Emission Properties of Selectively Grown Carbon Nanotubes for Electron Emitter in Microwave Power Amplifier

  • Han, Jae-Hee;Lee, Tae-Young;Kim, Do-Yoon;Yoo, Ji-Beom;Park, Chong-Yun;Choi, Jin-Ju;Jung, Tae-Won;Han, In-Taek;Kim, Jong-Min
    • 한국정보디스플레이학회:학술대회논문집
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    • 한국정보디스플레이학회 2003년도 International Meeting on Information Display
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    • pp.1021-1023
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    • 2003
  • We studied field-emission characteristics of CNTs under various pre-treatment with $NH_{3}$ plasma on the substrate. The turn-on electric field is the lowest value and field enhancement factor (${\beta}$) is he highest value in CNTs pre-treated by $NH_3$ plasma (80 W and 5 min). The field-emission property of CNTs grown on the Ta substrate is slightly better than on the W substrate.

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Carbon-Nanotube FED;Japanese National Project

  • Soichiro, Okuda
    • 한국정보디스플레이학회:학술대회논문집
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    • 한국정보디스플레이학회 2004년도 Asia Display / IMID 04
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    • pp.855-859
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    • 2004
  • The Japanese National Project "Carbon Nanotube FED" is developing a high image-quality and low power-consumption field emission display (FED) by applying carbon nanotube (CNT) to the electron source. A uniform electron source with a flat-film CNTs and fine structure triodes Fir suppressing the deviation of emission is required. For realizing an FED panel, it is also necessary to develop the glass-bulb technologies for vacuum sealing, and display technologies for driving the panel by circuit electronic and for evaluating the picture quality by measuring. By achieving these technologies, an FED compatible with conventional Cathode Ray Tubes (CRTs) will be realized.

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Measurement of Transient Electric Field Emission from a 245 kV Gas Insulated Substation Model during Switching

  • Rao, M. Mohana;Thomas, M. Joy;Singh, B.P.
    • Journal of Electrical Engineering and Technology
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    • 제2권3호
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    • pp.306-311
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    • 2007
  • The transient fields generated during switching operations in a Gas Insulated Substation (GIS) are associated with high frequency components in the order of few tens of MHz. These transient fields leak into the external environment of the gas-insulated equipment and can interfere with the nearby electronics. Measurements of the transient fields are thus required to characterise the interference caused by switching phenomena in such substations. In view of the above, E-field emission measurement during a switching operation has been carried out for a 245 kV GIS model, using a resonant dipole antenna and D-dot sensor. The characteristics of the E-fields i.e., frequency spectra and their levels have been analysed and are reported in the paper. Suitability of the measurements has been confirmed by comparing frequency spectra of the measured and computed transient fields.

DLC Emitter 전기적 특성 (Electric properties of DLC Emitter)

  • 이상헌
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 2009년도 제40회 하계학술대회
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    • pp.1312_1313
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    • 2009
  • In this study the fabrication technique of the planner field emission device structure with a DLC layer were studied. The bottom Mo electrode using electrochemical method on the DLC layer deposited using assist sputtering.

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이온빔 스퍼터링으로 제작된 다이아몬드성 카본 필름의 전계 방출 특성 (Field emission properties of diamond-like carbon films deposited by ion beam sputtering)

  • 안상혁;이광렬;전동렬
    • 한국진공학회지
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    • 제8권1호
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    • pp.36-42
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    • 1999
  • 이온빔 스퍼터링 방법으로 n-type si 기판에 고팅된, 수소를 함유하지 않은 다이아몬드성 카본 필름의 전계 방출 특성을 조사하였다. 필름의 구조나 두께에 관계없이 전계 방출 전류는 양극과 시편의 표면사이에서 발생하는 electrical breakdown에 의해 현저히 증가하였으며, 이때의 effective work function은 약 0.1eV의 작은 값을 가지고 있었다. 텅스텐 tip을 이용하여 breakdown에 의해 발생한 시편표면의 손상수위 근처를 scanning 하면서 전계 방출 전류를 측정하여, 전계 방출이 일어나는 정확한 위치를 확인하였다. 전계 방출은 breakdown에 의해 발생한 표면 손상 부위의 모든 곳에서 균일하게 일어나는 것이 아니라 특정 부위에서 집중적으로 관찰되었다. Auger electron spectroscopy와 SEM을 이용한 분석을 통해 손상 부위 중 Si과 C의 화합물이 형성된 곳에서만 절계 방출이 일어나고 있음을 알 수 있었으며, 손상부위의 형상변화는 전계 방출의 충분조건이 아니었다. 본 연구의 결과는 breakdown에 의한 전기 방출 전류의 증가는 시편 표면의 형상 변화에 의한 전계증진의 효과보다는 표면에서 발생하는 화학적 결합의 변화에 기인하고 있음을 보여준다.

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Vacuum In-line Sealing Technology of the Screen-printed CNT-FEA

  • Kwon, Sang-Jik;Kim, Tae-Ho;Shon, Byeong-Kyoo;Cho, Euo-Sik;Lee, Jong-Duk;Uh, Hyung-Soo;Cho, Sung-Hee;Lee, Chun-Gyoo
    • Journal of Information Display
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    • 제4권3호
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    • pp.6-11
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    • 2003
  • We have fabricated a carbon nanotube field emission display (CNT-FED) panel with a 2-inch diagonal size by using a screen printing method and vacuum in-line sealing technology. The sealing temperature of the panel was around 390$^{\circ}C$ and the vacuum level was obtained with 1.4x$10^{-5}$torr at the sealing. When the field emission properties of a fabricated and sealed CNT-FED panel were characterized and compared with those of the unsealed panel which was located in a test chamber of vacuum level similar with the sealed panel. As a result, the sealed panel showed similar I-V characteristics with unsealed one and uniform light emission with very high brightness at a current density of 243 ${\mu}A/cm^2$, obtained at the electric field of 10 V/${\mu}m$.

Current Density Equations Representing the Transition between the Injection- and Bulk-limited Currents for Organic Semiconductors

  • Lee, Sang-Gun;Hattori, Reiji
    • Journal of Information Display
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    • 제10권4호
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    • pp.143-148
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    • 2009
  • The theoretical current density equations for organic semiconductors was derived according to the internal carrier emission equation based on the diffusion model at the Schottky barrier contact and the mobility equation based on the field dependence model, the so-called "Poole-Frenkel mobility model." The electric field becomes constant because of the absence of a space charge effect in the case of a higher injection barrier height and a lower sample thickness, but there is distribution in the electric field because of the space charge effect in the case of a lower injection barrier height and a higher sample thickness. The transition between the injection- and bulk-limited currents was presented according to the Schottky barrier height and the sample thickness change.

Characteristics of Carbon Nanotube FED

  • Uemura, Sashiro;Yotani, Junko;Nagasako, Takeshi;Kurachi, Hiroyuki;Yamada, Hiromu;Ezaki, Tomotaka;Maesoba, Tsuyoshi;Nakao, Takehiro;Ito, Masaaki;Saito, Yahachi;Yumura, Motoo
    • 한국정보디스플레이학회:학술대회논문집
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    • 한국정보디스플레이학회 2004년도 Asia Display / IMID 04
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    • pp.860-865
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    • 2004
  • Field emission display(FED) using carbon nanotubes (CNT) as field emitters is expected to large-area panels with high luminance and low power consumption. In order to perform the uniform luminance with low driving voltage, we introduced a new electrode to apply higher electric potential over the CNT cathode in 2003.[1] In the study, we described the luminance uniformity of the panel and the improvement of emission uniformity by increasing the emission-site density. The luminance uniformity of the several ideal dots which were selected over the display area in the panel was 2.8%. [2] The CNT cathode was irradiated by excimer-laser, which was effective to improve emission uniformity and lower driving voltage. A prototype of CNT-FED character display was performed for middle size message displays. The prototype panel had 48 x 480-dots and the resolution was 1-mm. The panel realized high luminance at low power consumption. It will be important characteristics for legible and ubiquitous displays. [3]

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유한요소법과 전계-열전자 방출 모델에 의한 절연유체 내 공간전하 전파해석 (Analysis of Space Charge Propagation in a Dielectric liquid Employing Field-Thermal Electron Emission Model and Finite Element Method)

  • 이호영;이세희
    • 전기학회논문지
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    • 제58권10호
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    • pp.2011-2015
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    • 2009
  • In an insulating dielectric liquid such as transformer oil, space charge injection and propagation were analyzed under the Fowler-Nordheim and Richardson-Dushman's thermal emission charge injection conditions for blade-plane electrodes stressed by a step voltage. The governing equations were composed of all five equations such as the Poisson's equation for electric fields, three continuity equations for electrons, negative, and positive ions, and energy balanced equation for temperature distributions. The governing equations for each carrier, the continuity equations, belong to the hyperbolic-type PDE of which the solution has a step change at the space charge front resulting in numerical instabilities. To decrease these instabilities, the governing equations were solved simultaneously by the Finite Element Method (FEM) employing the artificial diffusion scheme as a stabilization technique. Additionally, the terminal current was calculated by using the generalized energy method which is based on the Poynting's theorem, and represents more reliable and stable approach for evaluating discharge current. To verify the proposed method, the discharge phenomena were successfully applied to the blade~plane electrodes, where the radius of blade cap was $50{\mu}m$.