• 한국재료학회지
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• 제14권3호
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• pp.186-190
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• 2004

An electron beam microcolumn composed of an electron emitter, micro lenses, scan deflector, and focus lenses have been fabricated and tested in the STEM mode. In this paper, we report a technique of precisely aligning the electron lenses by the laser diffraction patterns instead of the conventional alignment method based on aligner and STM. STEM images of a standard Cu-grid were observed using a fabricated microcolumn under both the retarding and accelerating modes.

• Applied Microscopy
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• 제45권3호
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• pp.150-154
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• 2015

Negative staining electron microscopy facilitates the visualization of small bio-materials such as proteins; thus, many electron microscopists have used this conventional method to visualize the morphologies and structures of biological materials. To achieve sufficient contrast of the materials, a number of imaging parameters must be considered. Here, we examined the effects of one of the fundamental imaging parameters, electron beam exposure time, on electron densities generated using transmission electron microscopy. A single site of a negatively stained biological sample was illuminated with the electron beam for different times (1, 2, or 4 seconds) and sets of micrographs were collected. Computational image processing demonstrated that longer exposure times provide better electron densities at the molecular level. This report describes technical procedures for testing parameters that allow enhanced evaluations of the densities of electron microscopy images.

• 한국진공학회:학술대회논문집
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• 한국진공학회 1998년도 제14회 학술발표회 논문개요집
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• pp.68-69
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• 1998

Nano-crystalline silicon(nc-Si) thin films were directly depposited by ion beam assisted electron beam depposition (IBAED) method. The visibe luminescence in IBAED sampples were originated from not an oxygen bond but Si nano-crystallites. And we can conclude that the ion beam would be contribute to the suppression of the Si-O bond formation.

• 전력전자학회:학술대회논문집
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• 전력전자학회 2003년도 춘계전력전자학술대회 논문집(2)
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• pp.942-948
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• 2003

This paper about the small electron beam irradiator for solar cell's efficiency. Many things are studied by method to increase conversion efficiency of solar cell. We selected electron beam by method for conversion efficiency of solar cell. Energy bands of this electron beam irradiator is 80keV(max.). And, solar cells that apply in this paper are crystal Si. Average efficiency of solar cell that applies in this experiment is 10$\%$. This system manufactured low energy electron beam irradiator. And, electron beam irradiation to solar cell in vacuum chamber of this irradiator. Irradiation area is 20*20 [mm2] by 40[keV].

• KSBB Journal
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• 제29권4호
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• pp.297-302
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• 2014

The autoclaving assisted by an irradiation pretreatment method was developed without toxic chemicals to produce fermentable sugars for their conversion to bioethanol. In the first step, electron beam irradiation (EBI) of rice straw was performed at various doses. The electron beam-irradiated rice straw was then autoclaved with DI water at $120^{\circ}C$ for 1 h. A total sugar yield of 81% was obtained from 300 kGy electron beam-irradiated rice straw after 72 h of enzymatic hydrolysis by Cellulase 1.5L (70 FPU/mL) and Novozyme-188 (40 CbU/mL). Also, the removal of hemicellulose and lignin was 32.0% and 32.5%, respectively. This result indicates that the environmentally-friendly pretreatment method of rice straw by an electron beam irradiation could be applied for bioethanol production in plant.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2004년도 추계학술대회 논문집
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• pp.401-404
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• 2004

The electron beam machining provides very high resolution up to nanometer scale, hence the E-beam writing technology is rapidly growing in MEMS and nano-engineering areas. In the optical column of the e-beam writer, there are several lenses condensing and focusing electron beams from electron gun with fringing magnetic fields. To achieve small spot size as 1-2 nm for higher power of electron beam, magnetic lenses should be designed considering their magnetic field distribution. In this paper, the magnetic field at two condenser lenses and object lens are calculated with finite element method and discussed its performances.

• 한국표면공학회지
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• 제43권4호
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• pp.170-175
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• 2010

The GaAs epitaxial layers were grown on Si(100) substrates by molecular beam epitaxy(MBE) using the two-step method. The Si(100) substrates were cleaned with different surface cleaning method of vacuum heating, As-beam, and Ga-beam at the substrate temperature of $800^{\circ}C$. Growth temperature and thickness of the GaAs epitaxial layer were $800^{\circ}C$ and 1 ${\mu}m$, respectively. The surface structure and epitaxial growth were observed by reflection high-energy electron diffraction(RHEED) and scanning electron microscope(SEM). Just surface structure of the Si(100) substrate cleaned by Ga-beam at $800^{\circ}C$ shows double domain ($2{\times}1$). RHEED patterns of the GaAs epitaxial layers grown on Si(100) substrates with cleaning method of vacuum heating, As-beam, and Ga-beam show spot-like, ($2{\times}4$) with spot, and clear ($2{\times}4$). From SEM, it is found that the GaAs epitaxial layers grown on Si(100) substrates with Ga-beam cleaning has a high quality.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2009년도 제40회 하계학술대회
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• pp.1483_1484
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• 2009

The electron collision cross sections for gases have been determined by electron beam and electron swarm method. Especially, measurements by electron swarm method is carried out by using the double shutter drift tube given by T.O.F. and Double shutter method.

• 접착 및 계면
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• 제11권4호
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• pp.162-167
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• 2010

본 연구에서는 셀룰로스계 섬유인 황마(jute)의 화학적 특성 및 열적 특성에 미치는 전자빔조사의 영향을 원소분석, ESR분석, ATR-FTIR 분광분석, 열중량분석 그리고 열기계분석을 통하여 탐구하였다. 전자빔 조사는 전자빔터널 내에서 콘베이어 카트를 이용한 연속식 방법에 의해 2~100 kGy까지 다양한 세기의 전자빔이 황마섬유다발에 일정하게 행하였다. 전자빔 처리는 황마섬유의 화학조성을 다소 변화시켰으며, 전자빔세기가 커질수록 황마섬유에 형성된 라디칼이 증가하는 것으로 확인되었다. 그러나 전자빔 조사는 황마섬유표면의 화학관능기를 크게 변화시키지 않는 것으로 판단되었다. 또한 전자빔 조사는 황마섬유의 열안정성과 열수축/팽창 거동에 영향을 주었으며, 그 거동은 전자빔세기에 의존하였다.

• 대한기계학회:학술대회논문집
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• 대한기계학회 2008년도 추계학술대회A
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• pp.1727-1732
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• 2008

We present a facile, yet versatile carbon nanofabrication method using electron beam lithography and resist pyrolysis. Various resist nanopatterns were fabricated using a negative electron beam resist, SAL-601, and were then subjected to heat treatment in an inert atmosphere to obtain carbon nanopatterns. Suspended carbon nanostructures were fabricated by wet-etching of an underlying sacrificial oxide layer. Free-standing carbon nanostructures, which contain 122 nm-wide, 15 nm-thick, and 2 ${\mu}m$-long nanobridges, were fabricated by resist pyrolysis and nanomachining processes. Electron beam exposure dose effects on resist thickness and pattern widening were studied. The thickness of the carbon nanostructures was thinned down by etching with oxygen plasma. An electrical biosensor utilizing carbon nanostructures as a conducting channel was studied. Conductance modulations of the carbon device due to streptavidin-biotin binding and pH variations were observed.