• Title/Summary/Keyword: Electron life time

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Real-Time Measurement of the Liquid Amount in Cryo-Electron Microscopy Grids Using Laser Diffraction of Regular 2-D Holes of the Grids

  • Ahn, Jinsook;Lee, Dukwon;Jo, Inseong;Jeong, Hyeongseop;Hyun, Jae-Kyung;Woo, Jae-Sung;Choi, Sang-Ho;Ha, Nam-Chul
    • Molecules and Cells
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    • v.43 no.3
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    • pp.298-303
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    • 2020
  • Cryo-electron microscopy (cryo-EM) is now the first choice to determine the high-resolution structures of huge protein complexes. Grids with two-dimensional arrays of holes covered with a carbon film are typically used in cryo-EM. Although semi-automatic plungers are available, notable trial-and-error is still required to obtain a suitable grid specimen. Herein, we introduce a new method to obtain thin ice specimens using real-time measurement of the liquid amounts in cryo-EM grids. The grids for cryo-EM strongly diffracted laser light, and the diffraction intensity of each spot was measurable in real-time. The measured diffraction patterns represented the states of the liquid in the holes due to the curvature of the liquid around them. Using the diffraction patterns, the optimal time point for freezing the grids for cryo-EM was obtained in real-time. This development will help researchers rapidly determine high-resolution protein structures using the limited resource of cryo-EM instrument access.

Defect evaluation of Fe metallic contamination in silicon wafers (Si 웨이퍼의 내부 금속 불순물 Fe의 결함분석)

  • 오민환;남효덕;김흥락;김동수;김영덕;김광일
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 2001.07a
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    • pp.578-581
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    • 2001
  • Silicon wafers using DRAM devices required for high cleaning technology and this cleaning technology was evaluated by defect level or electron life time. This paper examined the correlation of SPV(Surface Photo Voltaic Analyzer) which analyzes diffusion length of minority carriers and DLTS(Deep level Transient Spectroscope) which analyzes defect level.

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A Study on Electrode Construction of Compact Fluorescent Lamp (콤팩트 형광램프의 전극구조에 대한 고찰)

  • Shin, Sang-Wuk;Lee, Se-Hyun;Cho, Mee-Ryoung;Hwang, Myung-Keun
    • Proceedings of the Korean Institute of IIIuminating and Electrical Installation Engineers Conference
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    • 2004.05a
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    • pp.149-154
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    • 2004
  • In this paper, we observed an electrode structure that is an important element that decide life of compact fluorescent lamp. We measured winding and application type of electron emission material and electrode damage with SEM(Scanning Electron Microscope). From now on, we need to measure rather several difference aging-time sample than analyze a relation electrode between life

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Fatigue Crack Propagation Behavior for Electron Beam Welded Joint of SUS 321 (SUS 321 전자비임 용접부의 피로균열진전거동)

  • 김재훈
    • Journal of the Korean Society of Safety
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    • v.12 no.2
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    • pp.57-64
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    • 1997
  • Fatigue crack propagation behaviors and life prediction for SUS 321 plate and its electron beam weld metal were investigated using compact tension specimens. The larger the stress ratio is, the faster the crack propagates, but the variation of crack propagation rate decreases. The effect of stress ratio is greater in the slow crack propagation area than in the faster one. The crack propagation rate of electron beam weld metal is faster than that of base metal because of hardening, weld defect and residual stress in welding area. The crack propagation rate of transverse weld metal has a lower than that of base metal due to the effect of residual stress, but in the time of passing through welding area, has a higher rate. The crack propagation rate using $\Delta$K$_{eff}$ can be well plotted regardless of stress ratio. The fatigue life prediction method of considering crack closure more exactly predicts fatigue life than conventional one. conventional one.e.

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The electrical and optical properties of Xe plasma in flat lamp (평판형 광원에서 제논(Xe) 플라즈마의 전기적 광학적 특성 연구)

  • Pack, Gwang-Hyeon;Yang, Jong-Kyung;Lee, Jong-Chan;Chio, Yong-Sung;Park, Dae-Hee
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 2005.05b
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    • pp.60-64
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    • 2005
  • Discharge of the flat lamp lighting source research are requested very much. For improving brightness, life time, efficiency of flat lamp, plasma diagnosis of the flat lamp lighting source to understand property of lighting source is very important, distance of discharge electrode is 5.5mm and width is 16.5mm, we measured electron temperature and electron density measured with single langmuir probe in flat lamp, we tested the discharge from 100 Torr to 300 Torr pressure, the Pulse is rectangular pulse with frequency 20kHz and Duty ratio 20%. Resultly, electron temperature decreases and electron density increase as increase the gas pressure and electron temperature decreases and electron density increase as increase the voltage.

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Electrical and Optical Properties of Xe Plasma in Flat Lamp (평판형 광원에서 제논 플라즈마의 전기적 및 광학적 특성)

  • Choi, Yong-Sung;Lee, Kyung-Sup
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 2006.12a
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    • pp.71-74
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    • 2006
  • Discharge of the flat lamp lighting source research arc requested very much. For improving brightness, life time, efficiency of flat lamp, plasma diagnosis of the flat lamp lighting source to understand property of lighting source is very important. distance of discharge electrode is 5.5mm and width is 16.5mm, we measured electron temperature and electron density measured with single langmuir probe in flat lamp. we tested the discharge from 100 Torr to 300 Torr pressure. the Pulse is rectangular pulse with frequency 20kHz and Duty ratio 20%. Resultly, electron temperature decreases and electron density increase as increase the gas pressure and electron temperature decreases and electron density increase as increase the voltage.

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Electrical and Optical properties of Xe gas in flat lighting source (제논(Xe) 가스를 사용한 평판형 광원에서의 전기 및 광학적 특성 연구)

  • Pack, Gwang-Hyeon;Yang, Jong-Kyung;Lee, Jong-Chan;Choi, Yong-Sung;Park, Dae-Hee
    • Proceedings of the KIEE Conference
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    • 2005.07c
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    • pp.2190-2192
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    • 2005
  • Discharge of the flat lamp lighting source research are requested very much. For improving brightness, life time, efficiency of flat lamp, plasma diagnosis of the flat lamp lighting source to understand property of lighting source is very important. distance of discharge electrode is 5.5mm and width is 16.5mm, we measured electron temperature and electron density measured with single langmuir probe in flat lamp. we tested the discharge from 100 Torr to 300 Torr pressure. the Pulse is rectangular pulse with frequency 20kHz and Duty ratio 20%. Resultly, electron temperature decreases and electron density increase as increase the gas pressure and electron temperature decreases and electron density increase as increase the voltage.

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Xe Plasma property with flat lamp by Langmuir probe (정전탐침법을 사용한 평판형 광원의 제논(Xe)플라즈마 특성 연구)

  • Pack, Gwang-Hyeon;Yang, Jong-Kyung;Lee, Jong-Chan;Choi, Yang-Sung;Park, Dae-Hee
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 2005.07a
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    • pp.572-573
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    • 2005
  • Discharge of the flat lamp lighting source research are requested very much. For improving brightness. life time. efficiency of flat lamp and plasma diagnosis of the flat lamp lighting source to understand property of lighting source is very important. When a distance of discharge electrode is 5.5mm and width is 16.5mm. we measured electron temperature and electron density measured with single Langmuir probe in flat lamp. We tested the discharge from 100 Torr to 300 Torr pressure. The pulse type was rectangular with frequency 20kHz and duty ratio was 20%. In result. electron temperature decreases and electron density increased as increase the gas pressure and electron temperature decreases and electron density increase as increase the voltage.

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Quality Degradation of Semiconductor Transistors by 1MeV Electron Beam Exposure

  • Lee, Tae-Hoon;Gyuseong Cho
    • Proceedings of the Korean Nuclear Society Conference
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    • 1997.05b
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    • pp.401-406
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    • 1997
  • This paper presents preliminary results on the degradation of BJTs(Bipolar Junction Transistors) and MOSFETs(Metal Oxide Semiconductor Field Effect Transistors) by 1MeV electron beam. Exposure experimental results show that the change of minority-carrier life time in base region dominates the behavior of BJTs and that the buildup of charges in oxide region can affect the value of threshold voltage for MOSFETs. It was possible to correlate the decrease of the minority-carrier life time of BJTs with irradiation dose, while the shift of MOSFETs' threshold voltage was not only a function of charge buildup in oxide region.

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Xe Plasma Property with Flat Lamp by Langmuir Probe (단일탐침법을 사용한 평판형 광원의 제논 (Xe) 플라즈마 특성 연구)

  • Pack Gwang-Hyeon;Lee Jong-Chan;Hwang Myung-Keun;Choi Yong-Sung;Park Dae-Hee
    • The Transactions of the Korean Institute of Electrical Engineers C
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    • v.55 no.1
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    • pp.50-54
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    • 2006
  • The study on discharge of the flat lamp lighting source has been requested increasingly. To improve the brightness, life time and efficiency of flat lamp, the plasma diagnosis of flat lamp lighting source is very important. When a distance of discharge electrode is 5.5mm and width is 16.5mm, we measured electron temperature and electron density with single Langmuir probe in flat lamp. Pressure conditions to test the plasma discharge from 100 Torr to 300 Torr. The power supply was PDS-4000 with frequency 20kHz and duty ratio $20\%.$ Form these experimental results, electron temperature was decreased according to increase the gas pressure and the voltage while electron density was increased.