• Applied Microscopy
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• v.43 no.1
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• pp.9-13
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• 2013

The helium ion microscope (HIM) has recently emerged as a novel tool for imaging and analysis. Based on a bright ion source and small probe, the HIM offers advantages over the conventional field emission scanning electron microscope. The key features of the HIM include (1) high resolution (ca. 0.25 nm), (2) great surface sensitivity, (3) great contrast, (4) large depth-of-field, (5) efficient charge control, (6) reduced specimen damage, and (7) nanomachining capability. Due to the charge neutralization by flood electron beam, there is no need for conductive metal coating for the observation of insulating biological specimens by HIM. There is growing evidence that the HIM has substantial potential for high-resolution imaging of uncoated insulating biological specimens at the nanoscale.

• Proceedings of the Korea Air Pollution Research Association Conference
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• 2003.11a
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• pp.394-395
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• 2003

대기 중의 황산염 입자는 인체 건강에 좋지 않은 영향을 미칠 뿐 아니라, 지구에 유입되는 빛을 산란시키고 구름을 생성하는 핵으로 작용함으로서 직ㆍ간접적으로 햇빛을 차단하여 전지구적 기후 변화에 상당한 역할을 하는 것으로 알려져 있다. 황산염 입자는 대기 중 SO$_2$의 산화에 의해 주로 생성되는데, 지금까지의 대기 모델을 활용한 연구에 의하면 대기 중의 SO$_2$의 양에 비해 황산염의 양은 과소 평가되고 있다. 이는 대기 중 황산염의 생성에 대한 대기 화학 반응기전이 제대로 파악되지 않아서 global scale의 예측이 불확실하기 때문이다. (중략)

• Journal of Korean Ophthalmic Optics Society
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• v.11 no.2
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• pp.115-119
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• 2006

Electromagnetic shielding, transparent ITO coating layers have deposited on ocular lens substrate by magnetron sputtering. We investigated the effect induced by the substrate temperature on coating layer. The characteristics of the coating layers were analyzed using surface profiler, four-point probe, XRD, spectrophotometer and Auger Electron spectroscopy. As substrate temperature became higher, carrier concentration was increased and transmittance in the visible region was increased, too.

• Proceedings of the Korea Air Pollution Research Association Conference
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• 2002.11a
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• pp.352-353
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• 2002

최근 산업이 발달함에 따라 수도권을 비롯한 도시에서의 인구집중과 증가로 인한 운행 차량 수의 증가, 산업규모의 확대 둥으로 인해 대기분진 중 호흡성 또는 미세분진 농도의 증가가 관찰되고 있으며 이로 인한 주민건강 위해의 가능성이 제기되고 있다. 2.5$\mu\textrm{m}$ 이하의 미세 입자는 폐포내 침착율이 높으며, 유해성 가스 및 중금속을 쉽게 흡착하여 인체에 전달하는 매체가 되기도 하고, 빛을 흡수, 산란시키기 때문에 시정을 악화.시킨다. 따라서 도시대기의 입자상 물질의 물리적, 화학적 특성에 대해서 많은 연구가 진행되어 왔다. (중략)

• Journal of the Semiconductor & Display Technology
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• v.22 no.3
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• pp.52-61
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• 2023

We designed a novel ultra-miniaturized microcolumn structure having an stigmator to significantly improve throughput per unit time, which is the biggest disadvantage of microcolumns. We adopted the structure of the stigmator in the form of an electrostatic octupole electrode, and used an electrostatic quadrupole deflector with a relatively simple structure considering the increase in wiring due to the introduction of the stigmator. We have dramatically reduced the effect of astigmatism that occurs when the electron beam probe is scanned to the periphery of the target by introducing the stigmator between the control electrode and the deflector. As our numerical analysis simulation results, the field of view obtained as a result of this study is about 46.3% improved compared to our previous study, and the electron beam probe size of less than 10 nm was achieved in the entire field of view.

• Proceedings of the Korean Institute of IIIuminating and Electrical Installation Engineers Conference
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• 1998.11a
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• pp.131-133
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• 1998

Electron temperature, electron density and electron energy distribution function were measured in Radio-Frequency Inductively Coupled Plasma(RFICP) using a probe method. Measurements were conducted in argon discharge for pressure from 10 mTorr to 40 mTorr and input rF power from 100W to 600W and flow rate from 3 sccm to 12 sccm. Spatial distribution of electron temperature, electron density and electron energy distribution function were measured for discharge with same aspect ratio (R/L=2). Electron temperature was found to depend on pressure, but only weakly on power. Electron density and electron energy distribution function strongly depended on both pressure and power. Electron density and electron energy distribution function increased with increasing flow rate. Radial distribution of the electron density and electron energy distribution function were peaked in the plasma center. Normal distribution of the electron density, electron energy distribution function were peaked in the center between quartz plate and substrate. These results were compared to a simple model of ICP, finally, we found out the generation mechanism of Radio-Frequency Inductively Coupled Plasma.

• Proceedings of the Korea Air Pollution Research Association Conference
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• 2005.11a
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• pp.278-280
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• 2005

• Bulletin of the Korean Space Science Society
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• 1996.11a
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• pp.30-30
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• 1996

No Abstract, See Full Text

• Environmental Engineering Research
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• v.9 no.6
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• pp.299-307
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• 2004

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.31 no.2
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• pp.80-88
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• 2003

This paper describes the development of an ozone detector and an electron probe as parts of scientific payloads for sounding rockets such as the KSR-III. Each detector consists of sensor parts and electronic parts. We successfully carried out the calibration tests with developed ozone detector and the space plasma simulation chamber tests with electron detector. These payloads could be onboard the KSR-III and with measured data, it is expected and temperature profile over the Korean Peninsular.