• 전기학회논문지
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• 제58권4호
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• pp.777-782
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• 2009

In this paper, the effect of the secondary electron emission coefficient of Xe ion on glow discharge was examined by ID numerical simulation. The simulation was performed for two distinct structures, short and long gaps. The features of the glow discharges in the both structures, firing and sustain voltages, luminance, and efficiency, were analyzed at various secondary electron emission coefficient of Xe ion.

• 한국진공학회지
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• 제7권s1호
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• pp.7-14
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• 1998

Details are given of an study of the characteristics of field-induced electron emission from hydrogen-free high $sp^3$ content(>90%) amorphous diamond (a-D) film deposited on heavily doped ($\rho$<0.01 $\Omega\cdot\textrm{cm}$) n-type monocrystalline Si(111) substrate. It is demonstrated that a-D film has excellent electron field emission properties. Emission current can reach 0.9 $\mu$A at applied field as low as 1 V/$\mu\textrm{m}$, and emission current density can be obtained about several mA/$\textrm{cm}^2$. The emission current is stable when the beginning current is at 50 $\mu$A within 72 hours. Uniform fluorescence display of electron emission from whole face of the a-D film under the electric field of 10~20 V/$\mu\textrm{m}$ was also observed. It can be considered that the contribution of excellent electron emission property results from its smooth, uniform, amorphous surface and high $sp^3$ content of the a-D films.

• 한국전기전자재료학회논문지
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• 제27권1호
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• pp.45-49
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• 2014

We have fabricated white organic light-emitting diodes (OLEDs) using several thicknesses of electron-transport layer. The multi-emission layer structure doped with red and blue phosphorescent guest emitters was used for achieving white emission. 2,9-dimethyl-4,7-diphenyl-1,10-phenanthroline (BCP) was used as an electron-transport layer. The thickness of BCP layer was varied to be 20, 55, and 120 nm. The current efficiency, emission and recombination characteristics of multi-layer white OLEDs were investigated. The BCP layer thickness variation results in the shift of emission spectrum due to the recombination zone shift. As the BCP layer thickness increases, the recombination zone shifts toward the electron-transport layer/emission-layer interface. The white OLED with a 55 nm thick BCP layer exhibited a maximum current efficiency of 40.9 cd/A.

• Applied Science and Convergence Technology
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• 제24권6호
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• pp.273-277
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• 2015

We investigated secondary electron emission characteristics of ZnO thin films prepared by pulsed laser deposition method with respect to the ambient oxygen pressure and the substrate temperature during the deposition. X-ray diffraction, UV-Vis spectrometry, atomic force microscopy, and ${\gamma}$-FIB were used to examine the structural, optical transmission, surface morphology, and secondary electron emission properties of the films, respectively. The secondary electron emission coefficient of the ZnO films increases as the O/Zn ratio of the films increases which was thought to result from either the ambient oxygen pressure increase or the substrate temperature decrease and as the grain size of the films decreases. It was confirmed that ZnO has better secondary electron emission characteristics than those of MgO, which is currently widely used as a material for PDP protecting layers.

• 한국진공학회지
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• 제15권5호
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• pp.499-505
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• 2006

열 화학기상법으로 만든 GaN와 GaP 나노와이어에서 전계 방출과, 산소와 아르곤 분위기에서 안정성에 대해 조사하였다. GaN 나노와이어의 경우 산소 분위기에서 전계 방출이 급격하게 줄었으나, GaP에서는 그렇지 않았다. 두 나노와이어 모두 아르곤 분위기에서는 큰 변화가 없었다. GaP 나노와이어의 외부에 존재하는 산화물 층이 전자 방출 안정성에 크게 기여한 것으로 생각된다. 나노와이어에서 방출된 전자의 에너지 분포를 통해 반도체 나노와이어는 탄소 나노튜브와 그 전계 방출 메카니즘이 다름을 유추할 수 있었다.

• 한국정보디스플레이학회:학술대회논문집
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• 한국정보디스플레이학회 2002년도 International Meeting on Information Display
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• pp.658-661
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• 2002

Chemical species during growth of carbon nanotubes (CNTs) in direct current-plasma enhanced chemical vapor deposition were studied in details using $C_3H_4-NH_3$ and $CO-NH_3$ mixtures through optical emission spectroscopy (OES). In the $C_3H_4-NH_3$ system, the relative intensities of CN (388.3 nm) and CH (431.4 nm) decreased and that of $C_2$ (436 nm) increased, leading to $sp^2$-graphization into the CNT structure, leading to improvement of field emission property of CNTs. In the $CO-NH_3$ system, the trend is completely reversed. Attributing to the atomic oxygen for helping the graphitization of carbon, CNTs could be grown under the flow rate of CO (180 sccm)-$NH_3$ (10 sccm). Through these results, we suggest the growth mechanism in our system.

• 한국진공학회:학술대회논문집
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• 한국진공학회 2012년도 제42회 동계 정기 학술대회 초록집
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• pp.483-483
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• 2012

Recently, nonthermal bioplasma has been attracted by researchers due to their potentials to modulate cellular functions resulting in changes of biomolecular electron band structures as well as cell morphologies. We have investigated the secondary electron emission characteristics from the surface of the erythrocyte, i.e., red blood cell (RBC) with and without the nonthermal bioplasma treatment in morphological and biomolecular aspects. The morphologies have been controlled by osmotic pressure and biomolecular structures were changed by well known reactive oxygen species. Ion-induced secondary electron emission coefficient have been measured by using gamma-focused ion beam (${\gamma}$-FIB) system, based on the quantum mechanical Auger neutralization theory. Our result suggests that the nonthermal bioplasma treatment on biological cells could result in change of the secondary electron emission coefficient characterizing the biomolecular valence band electron energy structures caused by the cell morphologies as well as its surface charge distributions.

• Applied Microscopy
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• 제46권4호
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• pp.227-237
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• 2016

This investigation deals with the process of field electron emission from composite microemitters. Tested emitters consisted of a tungsten or carbon-fiber core, coated with a dielectric material. Two coating materials were used: (1) Clark Electromedical Instruments Epoxylite resin and (2) Epidian 6 Epoxy resin (based on bisphenol A). Various properties of these emitters were measured, including the current-voltage characteristics, which are presented as Fowler-Nordheim plots, and the corresponding electron emission images. A field electron microscope with a tip (cathode) to screen (anode) distance of 10 mm was used to electrically characterize the emitters. Measurements were carried out under ultra-high vacuum conditions with a base pressure of $10^{-6}$ Pascal ($10^{-8}$ mbar).

• Journal of Information Display
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• 제9권4호
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• pp.30-34
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• 2008

Field emitter arrays (FEAs) were developed using carbon nanotubes (CNTs) as electron emission sources. The CNTs were grown using a selective-positioning technique with a resist-protection layer. The light emission properties were studied through the electron emission of the CNTs on patterned islands, which were modulated with island diameter and spacing. The electron emission of CNT arrays with $5{\mu}m$ diameters and $10{\mu}m$ heights increased with increased spacing (from $10{\mu}m$ to $40{\mu}m$). The electron emission current of the $40-{\mu}m$-island-spacing sample showed a current density of 1.33 mA/$cm^2$ at E = 11 V/${\mu}m$, and a turn-on field of 7 V/${\mu}m$ at $1{\mu}A$ emission current. Uniform electron emission current and light emission were achieved with $40{\mu}m$ island spacing and $5{\mu}m$ island diameter.

• 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.