• 한국진공학회:학술대회논문집
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• 한국진공학회 2001년도 제21회 학술발표회 초록집
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• pp.174-174
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• 2001

• Journal of Electrical Engineering and Technology
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• 제7권1호
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• pp.97-102
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• 2012

To predict accurately the breakdown voltage in air at atmospheric pressure, a fully coupled finite element analysis combining the hydrodynamic diffusion-drift equations with Poisson's equation is proposed in the current paper. As three kinds of charged transport particles are nonlinearly coupled with spatial electric fields, the equations should be solved by an iterative numerical scheme, in which secondary effects, such as photoemission and photoionization, are considered. The proposed method has been successfully applied to evaluate the breakdown voltage in circular parallel-plane electrodes. Its validity has been proved through the comparison of the predicted and experimental results. The effects of numerical conditions of the initial charge, photoemission, and background ionization on the discharge phenomena are quantitatively assessed through Taguchi's design of experiment method.

• 한국정보디스플레이학회:학술대회논문집
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• 한국정보디스플레이학회 2009년도 9th International Meeting on Information Display
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• pp.173-176
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• 2009

We suggest a new protective layer for PDP consists of SrO and MgO double layer. This double layer structure protects SrO layer from the contamination by $H_2O$ or $CO_2$ in the air and enable SrO to play as the main cathode material. It was confirmed that the high secondary electron emission characteristics of SrO by Xe ion can bring considerable driving voltage reduction and improvement of luminance and luminous efficacy in PDP.

• 한국진공학회:학술대회논문집
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• 한국진공학회 1999년도 제17회 학술발표회 논문개요집
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• pp.236-236
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• 1999

AC-PDP(Plasma display Panel)는 기체 방전을 이용한 디스플레이로서 기체에 직접 노출되는 MgO 보호막의 이차전자 방출계수(${\gamma}$)는 AC-PDP의 방전특성을 결정짓는 중요한 요소이다. MgO 보호막의 이차전자 방출계수는 AC-PDP에 주입하는 기체의 종류, 결정 방향성과 표면오염상태등에 영향을 받는다. 본 연구에서는 MgO 보호막을 열처리한 상태와 열처리 하지 않은 상태를 ${\gamma}$-FIB 장치를 이용하여 2차전자방출 계수를 측정하여 비교하였다. 또한 24시간 MgO 보호막을 대기중에 방치하여 두었을 때 MgO 보호막의 표면오염상태에 대한 2차전자방출계수값을 측정하여 MgO 보호막의 표면오염에 대한 방전 전압특성저하가 어느정도인지를 알아보았다. 실험에 사용한 혼합기체는 Ne+Xe, He+Ne+Xe 혼합기체를 사용하였고, MgO 보호막은 21inch 규격의 실제 PDP Panel의 MgO 보호막을 사용하였다.

• 한국진공학회:학술대회논문집
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• 한국진공학회 2000년도 제18회 학술발표회 논문개요집
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• pp.201-201
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• 2000

AC-PDP(Plasma Display Panel)에 사용하는 MgO 보호막의 이차전자 방출계수(${\gamma}$)는 AC-PDP의 방전특성을 결정짓는 중요한 요소이다. MgO 보호막의 이차전자 방출계수는 AC-PDP에 주입하는 기체의 종류에 영향을 받는다. 현재 AC-PDP에는 방전특성의 향상과 VUV 발생을 위하여 He, Ne, Xe 등의 혼합기체가 사용되고 있으며, N 기체를 혼합하여 사용할 경우 더 좋은 발광효율을 얻을 수 있다는 보고가 있다. 이번 실험에서는 (100) 방향으로 배향된 MgO Bulk Crystal과 MgO 보호막의 이차전자방출계수를 ${\gamma}$-FIB 장치로 N2 기체혼합비율에 따라 측정하였다. 혼합기체는 Ne=N2 이원기체를 여러 가지 혼합 비율로 변화시켜가며 실험하였다. MgO 보호막은 실제 21inch 규격의 Panel을 사용하였다.

• 한국진공학회:학술대회논문집
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• 한국진공학회 2004년도 제26회 학술발표회 초록집
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• pp.135-135
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• 2004

• 한국진공학회:학술대회논문집
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• 한국진공학회 2000년도 제18회 학술발표회 논문개요집
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• pp.209-209
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• 2000

Carbon nanotubes have been intensively investigated for its fundamental and technical importances. Structural diversities and the related diverse physical properties with large aspect ratios are fascinating, For instance carbon nanotubes are metal and semiconductors depending on its chirality and furthermore the band gap can be tailored by the diamters. Several issues on its fundamental properties have been discussed. We will review some fundamental problems for band structures, molecular quantum wires, homojunctions, single electron tunneling, and quantum conductance. Several issues related to syntheis of carbon nanotubes including arc discharge, chemical vapor deposition, laser ablation will be extentively discussed. We will further review the applicability of carbon nanotubes on resonator, nanobalance, FET-type transistor, field emission displays electrode for secondary battery and hydrogen storage.

• 조명전기설비학회논문지
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• 제29권6호
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• pp.49-57
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• 2015

This paper presents the discharge characteristics and economic feasibility of a Dry $Air/O_2$ and a $N_2/O_2$ mixture gas in order to review $SF_6$ alternative. From AC discharge experiment in an quasi-uniform field, it was found that the optimal $N_2/O_2$ mixing ratio which breakdown voltage and surface flashover voltage were the highest was 70/30 and that the pressure dependence on the breakdown voltage was higher than that of the surface flashover voltage in the Dry $Air/O_2$ and the $N_2/O_2$ mixture gas. The mixing ratio (70/30) and the tendency of the pressure dependence were described in detail based on physical factors (impact ionization coefficient, electron attachment coefficient, secondary electron emission coefficient) involved in discharge mechanism and a electron source, respectively. In addition, the performance insulation and the economic feasibility of the Dry $Air/O_2$ and the $N_2/O_2$ mixture gas were discussed so that Dry $Air/O_2$ mixture gaswas more suitable than $N_2/O_2$ mixture gas to the $SF_6$ alternative.

• 한국진공학회:학술대회논문집
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• 한국진공학회 2014년도 제46회 동계 정기학술대회 초록집
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• pp.262.1-262.1
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• 2014

Lipid peroxidation induces functional deterioration of cell membrane and induces cell death in extreme cases. These phenomena are known to be related generally to the change of physical properties of lipid membrane such as decreased lipid order or increased water penetration. Even though the electric property of lipid membrane is important, there has been no report about the change of electric properties after lipid peroxidation. Herein, we demonstrate the molecular energy band change in red blood cell membrane through peroxidation by air-based atmospheric pressure DBD plasma treatment. Ion-induced secondary electron emission coefficient (${\gamma}$ value) was measured by using home-made gamma-focused ion beam (${\gamma}$-FIB) system and electron energy band was calculated based on the quantum mechanical Auger neutralization theory. The oxidized lipids showed higher gamma values and lower electron work functions, which implies the change of surface charging or electrical conductance. This result suggests that modified electrical properties should play a role in cell signaling under oxidative stress.

• 한국표면공학회지
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• 제38권1호
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• pp.7-13
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• 2005

Bismuth thin films were prepared on glass substrate with RF magnetron sputtering and effects of substrate temperature on surface morphology and their electrical transport properties were investigated. Grain growth of bismuth after nucleation and the onset of coalescense of grains at 393 K were observed with field emission secondary electron microscopy. Continuous thin films could not be obtained above 473 K because of grain segregation and island formation. Hall effect measurements showed that substrate heating yields the decrease of carrier density and the increase of mobility. Resistivity of bismuth film has its minimum (about 0.7 x 10/sup -3/ Ωcm) in range of 403～433 K. Annealing of bismuth films deposited at room temperature was carried out in a radiation furnace with flowing hydrogen gas. The change of resistivity was not significant due to cancellation of the decrease of carrier density and the increase of mobility. The abrupt change of electrical properties of film annealed above 523 K was found to be caused by partial oxidation of bismuth layer in x-ray diffraction analysis.