• 대한기계학회:학술대회논문집
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• 대한기계학회 2007년도 춘계학술대회A
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• pp.1271-1276
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• 2007

The most powerful analytical equipment usually comes at the cost of having the highest demand for space. Where electron microscopes has traditionally required a room to themselves, not just for reasons of their size but because of ancillary demands for pipes and service. The simple optical microscopes, of course, can occupy the desk-top, but because their performance is limited by the wavelength of light, their powers of magnification and resolution are inferior to that of the electron microscope. Mini SEM will sit comfortably on a desk-top but offers magnification and resolution performances much closer to that of a standard SEM. This new technique extends the scope of SEM as a high-resolution microscope, relatively cheap and widely available imaging tool, for a wider variety of samples.

• 진공이야기
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• 제2권1호
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• pp.17-20
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• 2015

In this article, a historical and scientific review on the development of an ultrafast electron microscope is supplied, and the challenges in further improvement of time resolution under sub-picosecond or even sub-femtosecond scale is reviewed. By combining conventional scanning electron microscope and femtosecond laser technique, an ultrafast electron microscope was invented. To overcome its temporal resolution limit which originates from chromatic aberration and Coulomb repulsion between individual electrons, a generation of electron pulse via strong-field photoemission has been investigated thoroughly. Recent studies reveal that the field enhancement and field accumulation associated with the near-field formation at sharply etched metal nanoprobe enabled such field emission by ordinary femtosecond laser irradiation. Moreover, a considerable acceleration reaching 20 eV with near-infrared laser and up to 300 eV acceleration with mid-infrared laser was observed, and the possibility to control the amount of acceleration by varying the incident laser pulse intensity and wavelength. Such findings are noteworthy because of the possibility of realizing a sub-femtosecond, few nanometer imaging of nanostructured sample.in silicon as thermoelectric materials.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 1998년도 봄 학술발표회논문집(II)
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• pp.677-682
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• 1998

Concrete is an inhomogeneous material consisting of larger aggregates and sand embedded in a cement paste matrix. In this study, an acoustic emission technique has been used to clarify the microscope failure mechanisms of concrete under three point bending test. AE source location has also been done to monitor the activities of internal damage and the progress of microscopic failure path during the loading. The relationship between AE characteristic and microscopic and microscopic failure mechanism is discussed.

• 한국재료학회지
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• 제6권6호
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• pp.605-609
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• 1996

MOS 소자의 얇은산화막(thin oxide)불량을 화학적으로 식각하지 않고 불량부위를 광전자방사(photon emission)반응을 이용하여 위치를 확인하고, 이곳을 FIB로 절단하여 불량부위의 단면을 관찰했다. 20nm 두께의 SiO2불량은 셀(cell)영역의 위치에 따른 의존성은 없고, 불량은 저전계의 입자(particle)성 불량과 중간전계의 Si 기판 핏(pit)과 관련된 불량이 주였다. 고전계에서는 전형적인 SiO2 산화막의 절연파괴가 일어난 것이 관찰된다.

• 대한치과보철학회지
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• 제43권3호
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• pp.338-351
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• 2005

Statement of problem. Accurate fit between the implant components is important because the misfit of the implant components results in frequent screw loosening, irreversible screw fracture, plaque accumulation, poor soft tissue reaction, and destruction of osseointegration. Purpose. This study is to evaluate the machining accuracy and consistency of the implant fixture/ abutment/screw interfaces of the internal connection system by using a Stereoscopic Zoom microscope and FE-SEM(field emission scanning electron microscope) Materials and methods. The implant systems selected in this study were internal connection type implants from AVANA(Osstem^{\circledR}), Bioplant(Cowell-Medi^{\circledR}), Dio(DIO^{\circledR}), Neoplant(Neobiotech 􀋓), Implantium(Dentium􀋓)systems. Each group was acquired 2 fixtures at random. Two piece type abutment and one piece type abutment for use with each implant system were acquired. Screw were respectively used to hold a two piece type abutment to a implant fixture. The implant fixtures were perpendiculary mounted in acrylic resin block. Each two piece abutment was secured to the implant fixture by screw and one piece abutment also secured to the implant fixture. Abutment/fixture assembly were mounted in liquid unsaturated polyester. All samples were cross-sectioned with grinder-polisher unit. Finally all specimens were analysed the fit between implant fixture/abutment/screw interfaces Results and conclusions. 1. Implant fixture/abutment/screw connection interfaces of internal connection systems made in Korea were in good condition. 2. The results of the above study showed that materials and mechanical properties and quality of milling differed depending on their manufacturing companies.

• 한국결정성장학회지
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• 제21권3호
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• pp.124-128
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• 2011

전기방사법을 이용하여 제조된 웹은 높은 비표면적 및 다공성으로 약물전달시스템에 적용하고자 널리 연구 되어지고 있다. 본 연구에서는 생체적합성을 가진 생분해성 고분자 Poly(lactic acid)(PLA)와 생체안정성을 가지는 재료인 $TiO_2$를 이용하여 복합소재를 제작하였다. 인체에 유해한 용매인 chloroform이 포함되어 있지 않은 복합화를 위하여 용융전기방사법을 이용하여 나노섬유를 제작하였다. 이렇게 제조된 PLA/$TiO_2$ web을 scanning electron microscope(SEM)와 field emission transmission electron microscope(FE-TEM)을 이용하여 섬유의 모양을 확인하였고, X-ray diffractometer(XRD)판 이용하여 PLA/$TiO_2$ web의 결정구조를 분석하였다.

• 한국정보통신학회:학술대회논문집
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• 한국해양정보통신학회 2008년도 추계종합학술대회 B
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• pp.95-99
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• 2008

반도체 소자의 소형화에 따라 낮은 비저항을 가진 구리가 ULSI의 금속배선으로 사용되고 있다. 구리선의 비저항은 RC delay와 집적회로의 신호전달에 영향을 미치게 된다. 본 논문에서는 전기도금 된 구리박막의 비저항에 대해 전해액이 미치는 영향을 조사하였다. 4탐침 표면저항측정기로 비저항을 평가하였고, XRD (X-ray Diffraction), AFM (Atomic Force Microscope), FE-SEM (Field Emission Scanning Electron Microscope), XPS (X-ray Photoelectron Spectroscopy)로 박막의 특성을 조사하였다. 실험한 결과, 전해액의 조건이 전기도금으로 증착된 낮은 비저항을 갖는 구리박막의 형성에 있어 중요한 역할을 하는 것을 확인하였다.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2011년도 제42회 하계학술대회
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• pp.1408-1409
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• 2011

Carbon nanotubes (CNTs) were grown on conical tip substrates by using various methods such as electrophoretic deposition, dip-coating, and spray. The scanning electron microscope measurement showed that the spray method ascertained the most uniform deposition of CNTs. The CNT-emitter that was fabricated by the spray method revealed the lowest turn on voltage of electron emission and the highest emission current. In addition, the spray-produced CNT emitter showed the most stable long-term emission characteristics.

• 한국정보디스플레이학회:학술대회논문집
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• 한국정보디스플레이학회 2003년도 International Meeting on Information Display
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• pp.859-862
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• 2003

Well-aligned multiwall carbon nanotubes (MWCNTs) were prepared at low temperature of 400 $^{\circ}C$ by utilizing a radio frequency plasma-enhanced chemical vapor deposition (rf-PECVD) system. The MWCNTs were treated by an external rf plasma source and an ultra-violet laser in order to modify structural defect of carbon nanotube and to ablate possible contamination on carbon nanotube surface. Structural properties of carbon nanotubes were investigated by using a scanning electron microscopy (SEM), Raman spectroscopy, Fourier transformer Infrared spectroscopy (FTIR) and transmission electron microscope (TEM). In addition, the emission properties of the MWNTs were measured for the application of field emission display (FED) in near future. Various post treatments were found to improve the field emission property of carbon nanotubes.

• 센서학회지
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• 제16권4호
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• pp.307-312
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• 2007

The films of Er-doped ZnO (ZnO:Er) were prepared onto MgO wafers by ultrasonic spray pyrolysis at $550^{\circ}C$. The concentration of Er in the deposition source varied from 0.5 wt% to 3.0 wt%. The crystallographic properties and surface morphologies of the films were investigated by X-ray diffraction (XRD) and scanning electron microscope (SEM), respectively. The properties of photoluminescence (PL) for the films were investigated by dependence of PL spectra on the Er concentration in the films. The films were grown as polycrystalline with a dominant direction of [002]. The grain size of the films were reduced by Er-doping. Er-doping enhanced the ultraviolet emission of ZnO:Er films. The ZnO:Er films prepared with the deposition source of 2.0 wt% Er showed the strongest ultraviolet light emission peak among the films in this study.