• 대한기계학회:학술대회논문집
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• 대한기계학회 2007년도 춘계학술대회A
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• pp.502-505
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• 2007

PMMA has been extensively adopted in Nano Imprint Lithography(NIL). PMMA nano-structures experience severe mechanical load and deformation during NIL process, and understanding its mechanical behavior is very important in designing and optimizing NIL process. One of the most promising techniques for characterizing the mechanical behavior of nano structures is nano pillar compression test. In this study, the mechanical behaviors of PMMA pillars during compression test are analyzed using Molecular Dynamics. Two methods for simulation of PMMA nano pillars are proposed. The stress-strain relationship of nano-scale PMMA structure is obtained based on CVFF(Covalent Valence Force Fields) potential and the dependency of the applied strain rate on the stress-strain relationship is analyzed. The obtained stress-strain relationships can be useful in simulating nano-scale PMMA structures using Finite Element Method(FEM) and understanding the experimental results obtained by compression test of PMMA nano pillars.

• 한국정밀공학회지
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• 제21권3호
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• pp.163-170
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• 2004

Atomic force microscope (AFM) techniques are increasingly used fur tribological studies of engineering surfaces at scales ranging from atomic and molecular to micro-scale. Recently, AFM with suitable tips is being used for nano fabrication/nano machining purposes. In this paper, machining characteristics of silicon were investigated by nano indentation and nano scratch. Nano-scale material removal mechanisms are studied and the Taguchi method was introduced to acquire optimum parameters for nano machining. Also, Acoustic Emission (AR) is used for the monitoring of nano machining.

• 대한전자공학회논문지SD
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• 제42권12호
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• pp.1-8
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• 2005

본 연구에서는 측정된 S-파라미터로부터 추출된 Nano-scale MOSFET 등가회로 파라미터의 scaling 방정식을 사용하여 차단주파수의 게이트 길이 종속성을 모델화하였다. 모델된 차단주파수는 게이트 길이가 줄어듬에 따라서 크게 증가하다가, 점점 증가율이 크게 감소하는 경향을 보였다. 이는 게이트 길이가 감소함에 따라 내부전달시간은 크게 줄어들지만, 외부 기생 충전시간은 상대적으로 조금씩 감소하기 때문이다. 이와 같은 새로운 게이트길이 종속 모델은 Nano-scale MOSFET의 RF성능을 최적화시키는 데 큰 도움이 될 것이다.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2003년도 춘계학술대회 논문집
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• pp.1211-1214
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• 2003

The film is prepared by electron cyclotron resonance chemical vapor deposition (ECRCVD) employing CH$_4$ and H$_2$ gases. It is deposited by the control of microwave plasma power, gas flow ratio, deposition pressure, and In-situ thermal treatment temperature. The structure of a-C:H (hydrogenated amorphous carbon) thin film is analysed by FT-IR spectroscopy. The fraction sp$^3$ versus sp$^2$ bonding is very important to clear up the surface and interrace of a-C:H film properties such as nano-scale friction behavior. The sp$^3$ versus sp$^2$ bonding of a-C:H thin film is dependent on the deposition conditions, therefore. nano-scale friction behavior is dependent on the deposition conditions.

• 한국추진공학회:학술대회논문집
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• 한국추진공학회 2007년도 제28회 춘계학술대회논문집
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• pp.45-48
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• 2007

기존에 사용되는 피에조 타입의 센서는 추력의 측정 범위가 제한되어 있으므로 이를 개선하고자 레이져 변위측정기와 cantilever를 이용하여 변위 측정 장치를 개선하였고, 스테인레스 캐필러리를 이용하여 추력 모델을 만든 후 추력을 측정하였다. 이와 더불어 extrude shape의 노즐을 갖는 마이크로 추력 장치를 PMMA(Polymethyl methacrylate)를 이용하여 공정하였으며, 매니스커스의 형상 변화를 관찰하였다.

• 한국분말야금학회:학술대회논문집
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• 한국분말야금학회 2006년도 Extended Abstracts of 2006 POWDER METALLURGY World Congress Part 1
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• pp.36-37
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• 2006

This study aims to investigate the usage of nano-scale particles in a micro metal injection molding ($\mu$-MIM) process. Nanoscale particle is effective to improve transcription and surface roughness in small structure. Moreover, the effects of hybrid micro/nano particles, Cu/Cu and SUS/Cu were investigated. Small dumbbell specimens were produced using various feedstocks prepared by changing binder content and fraction of nano-scale Cu particle (0.3 and $0.13{\mu}m$ in particle size). The effects of adding the fraction of nano-scale Cu powder on the melt viscosity of the feedstock, microstructure, density and tensile strength of sintered parts were discussed.

• 진공이야기
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• 제5권1호
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• pp.4-8
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• 2018

Many devices based on magnetism such as power generators and motors are frequently used in real life. Magnetic materials at nano-scale can be utilized as storage devices such as magnetic tapes and hard disk drives as well as spintronics. In addition to spintronics, magnetic biosensors are another interesting application of magnetic devices at nano-scale. Here, we briefly review magnetic nano-biosensors including Hall-effect sensors, giant magnetoresistive sensors, and tunnel magnetoresistive sensors for many biomedical applications.

• 한국자기학회:학술대회 개요집
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• 한국자기학회 2003년도 하계학술연구발표회 및 한.일 공동심포지엄
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• pp.76-77
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• 2003

• 한국분말재료학회지
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• 제21권3호
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• pp.207-214
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• 2014

In this study, nano-scale copper powders were reduction treated in a hydrogen atmosphere at the relatively high temperature of $350^{\circ}C$ in order to eliminate surface oxide layers, which are the main obstacles for fabricating a nano/ultrafine grained bulk parts from the nano-scale powders. The changes in composition and microstructure before and after the hydrogen reduction treatment were evaluated by analyzing X-ray diffraction (XRD) line profile patterns using the convolutional multiple whole profile (CMWP) procedure. In order to confirm the result from the XRD line profile analysis, transmitted electron microscope observations were performed on the specimen of the hydrogen reduction treated powders fabricated using a focused ion beam process. A quasi-statically compacted specimen from the nano-scale powders was produced and Vickers micro-hardness was measured to verify the potential of the powders as the basis for a bulk nano/ultrafine grained material. Although the bonding between particles and the growth in size of the particles occurred, crystallites retained their nano-scale size evaluated using the XRD results. The hardness results demonstrate the usefulness of the powders for a nano/ultrafine grained material, once a good consolidation of powders is achieved.

• 한국자기학회지
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• 제14권4호
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• pp.149-161
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• 2004

나노기술과 정보기술의 융합은 이제 성숙 단계에 있는 정보화시대에 중요한 역할을 할 것으로 예상된다. 특히, 한국 산업에서의 정보 기술의 역할을 고려할 때, NT-IT 기술 융합은 매우 중요하다. 나노 소재는 그 크기가 나노미터 크기로 작은 것을 의미하며, 나노 크기에서 독특한 물성을 나타내는 특성을 가지고 있다 자기조립 기술을 활용하여 보텀업 공정을 수행하여 나노 크기의 정보 소재 및 소자를 구현한다. 이러한 기술은 생물체 등에서 일어나는 원자나 분자의 자기 조립 현상과 유사하다. 유기. 무기 템플릿을 이용한 정보 소재 개발 연구는 Guided Self Assembly유기물 나노 템플릿의 개발 및 AAO무기물 나노 템플릿을 활용한 나노 구조물 형성과 이를 응용한 정보기술과의 융합에 관해 연구이다. Nano structuring을 위해 Electroforming, Sol-gel processing, ionized Physical vapor deposition, ion beam implantation 법 등을 사용하며, 정보기술에 필요한 핵심 요소 기술을 개발한다. 형성된 Nano structure의 전기적 특성 평가 및 미세 구조 분석 및 응용을 고려한 소자 특성 평가를 통해서, IT분야에 적용 가능한 정보소재를 개발한다.