• 한국진공학회:학술대회논문집
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• 한국진공학회 2009년도 제38회 동계학술대회 초록집
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• pp.475-475
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• 2010

We have generated Ar plasma in dense plasma focus device with coaxial electrodes for extreme ultraviolet (EUV) lithography and investigated an emitted visible light for electro-optical plasma diagnostics. We have applied an input voltage 4.5 kV to the capacitor bank of 1.53 uF and the diode chamber has been filled with Ar gas of pressure 8 mTorr. The inner surface of the cylindrical cathode has been attatched by an acetal insulator. Also, the anode made of tin metal. If we assumed that the focused plasma regions satisfy the local thermodynamic equilibrium (LTE) conditions, the electron temperature and density of the coaxial plasma focus could be obtained by Stark broadening of optical emission spectroscopy (OES). The Lorentzian profile for emission lines of Ar I of 426.629 nm and Ar II of 487.99 nm were measured with a visible monochromator. And the electron density has been estimated by FWHM (Full Width Half Maximum) of its profile. To find the exact value of FWHM, we observed the instrument line broadening of the monochromator with a Hg-Ar reference lamp. The electron temperature has been calculated using the two relative electron density ratios of the Stark profiles. In case of electron density, it has been observed by the Stark broadening method. This experiment result shows the temporal behavior of the electron temperature and density characteristics for the focused plasma. The EUV emission signal whose wavelength is about 6 ~ 16 nm has been detected by using a photo-detector (AXUV-100 Zr/C, IRD). The result compared the electron temperature and density with the temporal EUV signal. The electron density and temperature were observed to be $10^{16}\;cm^{-3}$ and 20 ~ 30 eV, respectively.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2006년도 영호남 합동 학술대회 및 춘계학술대회 논문집 센서 박막 기술교육
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• pp.86-90
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• 2006

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 f1at 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 have measured electron temperature and electron density measured with single Langmuir probe in flat lamp. We have tested the discharge from 100 Torr to 300 Torr pressure. The pulse is rectangular pulse with frequency 20kHz and duty ratio 20%. In result, electron temperature decreases and electron density increase as increase the gas pressure and electron temperature decreases and electron density increase as increase the voltage.

• 한국정보디스플레이학회:학술대회논문집
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• 한국정보디스플레이학회 2008년도 International Meeting on Information Display
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• pp.1602-1605
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• 2008

We considered most general electron emission caused by temperature as well as electric field with a free electron gas model. The total electron emission current density comes from field emission effect where electron energy is lower than vacuum and from thermionic emission effect where electron energy is higher than vacuum. The total electron emission current density is shown as a function of temperature for constant electric field, and as a function of electric field for constant temperature.

• 전자공학회논문지D
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• 제35D권2호
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• pp.40-51
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• 1998

Electron transport properties are investigated by Monte Carlo simulation in n-HgCdTe. The material is easily degenerated at low temperature or being slightly doped, and is characterized by small band gap and large nonparabolic factor. The degeneracy is incorporated in the Monte Carlo simulation by taking into account the electron-electron scattering and the pauli exclusion principle. In the conventional method, however, the electron-electron scattering rate was developed under the assumption of parabolic conduction band. A new formulation of the electron-electron scattering rate is develop considering the band nonparabolicity and overlap integral. The electron-electron scattering effects on the electron distribution,impact ionization coefficienty, electron temperature, drift velocity and electron energy are presented.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2005년도 춘계학술대회 논문집
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• pp.41-45
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• 2005

In this paper, parameters of electron temperature and density for the mercury-free lighting-source were measured to diagnosis and analyze in Xe based inductively coupled plasma(ICP). In results at several dependences of 20~100 mTorr Xenon pressure, 50~200W RF power and horizontal distribution were especially mentioned. When Xe pressure was 20mTorr and RF power was 200W, the electron temperature and density were respectively 3.58eV and $3.56{\times}10^{12}cm^{-3}$. The key parameters of Xe based ICP depended on Xe pressure more than RF power that could be verified. A high electron temperature and low electron density with a suitable Xe pressure are indispensible parameters for Xe based ICP lighting-source.

• 천문학회보
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• 제45권1호
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• pp.52.2-52.2
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• 2020

At quasi-perpendicular shocks in the high-�� (��=Pgas/Pmag~100) intracluster medium (ICM), various microinstabilities occur by the temperature anisotropies and/or drift motions of plasma. In the downstream, the Alfvén ion cyclotron instability (AIC) due to the ion temperature anisotropy (Ti⊥>Ti║) is triggered by shock-reflected ions, the whistler instability (WI) is driven by the electron temperature anisotropy (Te⊥>Te║) as a consequence of the shock compression of magnetic fields, and the mirror instability is generated due to the ion and/or electron temperature anisotropy. At the shock foot, the modified two stream instability (MTSI) is possibly excited by the cross-field drift between ions and electrons. In the upstream, electron firehose instability (EFI) is driven by the electron temperature anisotropy or the relative drift between incoming and reflected electrons. These microinstabilities play important roles in the particle acceleration in ICM shocks, so understanding of the microinstabilities and the resultant plasma waves is essential. In this study, based on a linear stability analysis, the basic properties of the microinstabilities in ICM shocks and the ion/electron scale fluctuations are described. We then discuss the implication of our work on the electron pre-acceleration in ICM shocks.

• Journal of Astronomy and Space Sciences
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• 제15권2호
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• pp.401-415
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• 1998

1998년 6월 11일 오전 10시(KST)에 태안 반도(37。N, 126。E)에서 발사된 국산 로켓 KSR-II는 73km에서 130km고도에 걸쳐 전자 밀도, 전자 온도, 부동 전위 등을 관측하는데 성공하였다. 이 지역은 이온 층의 E-region에 해당하는 지역으로 전자 온도가 낮고 특히 Probe의 오염 효과에 의해 오차가 생길 수 있기 때문에 전자 온도에 대한 정확한 데이터를 얻기가 쉽지 않다. 본 실험에서 사용된 장비는 Langmuir Probe (LP)와 Electron Temperature Probe (ETP)로 두 가지 서로 다른 probe를 통해 얻은 전자 온도를 비교하여 검증된 전자 온도를 구할 수 있었다. 실험 결과 전자 밀도는 약 90km지점에서 급격히 증가하여 약 102km지점에서 최대 전자 밀도를 갖고 이 이상의 고도에서는 점차 감소하는 것으로 나타났다. 이는 최대 전자밀도가 110km에서 나타나는 IRI(International Reference Ionosphere)95-model이나 PIM(Parameterized Ionospheric Model)과 비교해 보면 다소 낮은 고도에서 최대 전자 밀도가 존재하였음을 알 수 있으며 측정된 값은 모델 계산에 비해 약간 큰 값을 갖는 것으로 나타났다. 한편 ETP로 측정된 전자 온도는 200$^{\circ}$K에서 700$^{\circ}$K에서 LP에 의한 교란 효과로 추정되는 요동현상을 보였으며 이를 제외하면 전자 온도가 고도에 따라 다소 증가하는 경향을 볼 수 있었다. LP를 통해 구한 전자 온도는 125km이상의 고도에서 ETP를 통하여 구한 전자 온도와 어는 정도 일치한다는 점에서 신뢰할 만한 측정값을 얻었다고 판단된다.

• KIEE International Transactions on Electrophysics and Applications
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• 제2C권5호
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• pp.246-252
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• 2002

Two-dimensional steady state simulations of planar type radio frequency inductively coupled plasma (RFICP) have been performed. The characteristics of RFICP were investigated in terms of power transfer efficiency, equivalent circuit analysis, spatial distribution of plasma density and electron temperature. Plasma density and electron temperature were determined from the equations of ambipolar diffusion and energy conservation. Joule heating, ionization, excitation and elastic collision loss were included as the source terms of the electron energy equation. The electromagnetic field was calculated from the vector potential formulation of ampere's law. The peak electron temperature decreases from about 4eV to 2eV as pressure increases from 5 mTorr to 100 mTorr. The peak density increases with increasing pressure. Electron temperatures at the center of the chamber are almost independent of input power and electron densities linearly increase with power level. The results agree well with theoretical analysis and experimental results. A single turn, edge feeding antenna configuration shows better density uniformity than a four-turn antenna system at relatively low pressure conditions. The thickness of the dielectric window should be minimized to reduce power loss. The equivalent resistance of the system increases with both power and pressure, which reflects the improvement of power transfer efficiency.

• 한국조명전기설비학회:학술대회논문집
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• 한국조명전기설비학회 1989년도 추계학술발표회논문집
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• pp.19-24
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• 1989

The electron energy distribution function in mercury discharge positive columns are calculated numerically from the Boltzmann eqation under a set of parameters, such as the electron temperature to. the atomic temperature Tw. the electron number density no. and the electric field E. Especially, using the approximation that collision cross sections only depend on the energy, the calculated electron energy distribution function was shown that it falls off rapidly in the high energy tail.

• 한국정밀공학회지
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• 제32권4호
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• pp.387-394
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• 2015

We analyze heat generation as well as temperature distribution induced by accelerated electron impact on a target in a closed x-ray tube. For the sake of accuracy, we use Monte carlo analysis. This method gives accurate energy deposit in a medium with additional information such as secondary and backscattered electron as well as their paths. A Tungsten coated layer is divided by small rectangular cell which accumulate energy loss of primary electron beam. The cells and their accumulated energy datum are used for the input of finite element analysis. The Maximum temperature rising and temperature distribution were analyzed by transient heat analysis. Some temperature parameters such as target size and coating thickness were varied to investigate temperature sensitivity. Temperatures were compared each other to find primary variable that affect temperature rising on the x-ray target. The results will be helpful in development highresolution x-ray tube and related industries.