• Proceedings of the KWS Conference
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• 1996.05a
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• pp.10-12
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• 1996

• Journal of Welding and Joining
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• v.18 no.5
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• pp.18-24
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• 2000

• Electrical & Electronic Materials
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• v.7 no.5
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• pp.425-429
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• 1994

In this paper, we study on the plasma polymerized styrene as a negative electron-beam resist. Plasma polymerized thin film was prepared using an interelectrode inductively coupled gas-flow type reactor. We show that polymerization parameters of thin film affect sensitivity and etching resistance of the resist. Molecular weight distribution of plasma polymerized styrene is 1.41-3.93, and deposition rates of that are 32-383[.angs./min] with discharge power. Swelling and etching resistance becomes . more improved with increasing discharge power during plasma polymerization. Etch rate by RIE is higher than that by plasma etching.

• Design & Manufacturing
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• v.14 no.2
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• pp.62-68
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• 2020

Recently, research on precise parts required in aerospace, ship, and automobile industries has been actively conducted. In this paper, electron beam drilling machining parameters were selected and experiments were conducted to compare processing characteristics analysis according to machining parameters through machining experiments of a vaporization amplification sheet to which STS 304 was applied. Also, as a result of measuring the machining. As the thickness gradually increased, it was confirmed that the electron beam could not reach the vaporization amplification sheet and thus melted on the surface of the material. As a result of the experimental analysis, it was analyzed that the vaporization explosion reaction of the vaporization amplification sheet was not normally performed due to the working distance (WD) according to the material thickness.

• Food Science and Preservation
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• v.16 no.2
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• pp.198-203
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• 2009

We examined the effects of electron-beam irradiation(0.5, 1, 2, or 5 kGy) on microbiological, physicochemical, and sensory quality characteristics of Myungran Jeotgal, Korean fermented seafood, during subsequent storage at $4^{\circ}C$ for 2 weeks. Viable counts of total aerobic bacteria, yeasts and molds, and total coliforms fell, after irradiation, to below detection limits($10^1CFU/g$). The pH of irradiated Myungran Jeotgal was maintained during storage but that of the non-irradiated control decreased. Sensory quality was not affected by electron-beam irradiation, except that color scores in samples irradiated with 2 and 5 kGy were lower than that of the control. Lipid oxidation tended to rise with increased irradiation dose and longer storage periods. The results suggest that electron-beam irradiation can be used to extend the shelf-life of Myungran Jeotgal without apparent quality attribute deterioration. However, means of preventing lipid oxidation resulting from electron-beam irradiation need consideration if irradiation is to find further applications in the food industry.

• Journal of the Korean Vacuum Society
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• v.7 no.s1
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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.

• Journal of the Korean Society of Manufacturing Technology Engineers
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• v.8 no.2
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• pp.100-107
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• 1999

End milling experiments are conducted to investigate characteristics of laser beam signals due to tool fracture. The laser beam signals are obtained with adapt focusing of tool. Tool states are identified wit h scanning electron microscopy and optical microscopy. It is demonstrated that the laser beam signals provide reliable informations about the cutting processes and tool states. Moreover, tool fracture can be detected successfully using coefficient of variation.

• Applied Microscopy
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• v.46 no.4
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• pp.171-175
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• 2016

A distinctive neuronal network in the brain is believed to make us unique individuals. Electron microscopy is a valuable tool for examining ultrastructural characteristics of neurons, synapses, and subcellular organelles. A recent technological breakthrough in volume electron microscopy allows large-scale circuit reconstruction of the nervous system with unprecedented detail. Serial-section electron microscopy-previously the domain of specialists-became automated with the advent of innovative systems such as the focused ion beam and serial block-face scanning electron microscopes and the automated tape-collecting ultramicrotome. Further advances in microscopic design and instrumentation are also available, which allow the reconstruction of unprecedentedly large volumes of brain tissue at high speed. The recent introduction of correlative light and electron microscopy will help to identify specific neural circuits associated with behavioral characteristics and revolutionize our understanding of how the brain works.

• Proceedings of the KIEE Conference
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• 2006.07c
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• pp.1552-1553
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• 2006

A thermionic gun of injector linac for pohang accelerator laboratory is required to generate beam pulse width less than 1 nsec. The gun uses cathode-grid assembly(EIMAC Y824) and operates up to 80 kV anode voltage. In order research characteristics of the electron gun, emission current from gun wear measured by the wall current monitor. In this paper the pulser system and characteristics of the emission current in region from 30 mA to 15 A are described.

• Proceedings of the Korean Vacuum Society Conference
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• 2010.02a
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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.