• 한국정보디스플레이학회:학술대회논문집
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• 한국정보디스플레이학회 2009년도 9th International Meeting on Information Display
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• pp.1220-1223
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• 2009

The effect of silver (Ag) nano-particles on OLEDs was investigated by using a finite difference time domain (FDTD) tool. The proposed OLEDs employed Ag nanoparticles thermally deposited in a high vacuum on a cathode. The emission rate of the exciton was improved by 1.8 fold compared to the conventional OLEDs without Ag nano-particles. Less spacing between the dipole source and the Ag nano-particles resulted in a larger emission rate of the exciton in the OLED with nano-particles. The size of the Ag nano-particles was proportional to the emission rate of the exciton in a range of nano-meter scale of nano-particles. The enhancement of the emission rate of the exciton due to Ag nano-particles caused the improvement in the efficiency of the proposed OLED.

• 한국진공학회:학술대회논문집
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• 한국진공학회 2009년도 제37회 하계학술대회 초록집
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• pp.146-146
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• 2009

• 한국정밀공학회지
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• 제20권12호
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• pp.19-24
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• 2003

• Journal of Nutrition and Health
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• 제42권8호
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• pp.740-749
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• 2009

본 연구는 ultra-fine pulverizer 또는 nano-scale pulverizer로 초미세분쇄시켜 입자크기가 감소된 옥수수전분의 섭취로 인한 생리적 기능성을 탐색한 결과는 다음과 같다. 1) 각 실험식이군의 식이 섭취량은 UFC군, NAC군은 차이가 없었으며, NSC군에서 유의하게 낮았다. NSC군의 식이 섭취량이 낮았음에도 불구하고 체중증가량이 많아 식이효율은 NSC군에서 가장 높았다. 2) 간, 신장의 무게는 UFC군 > NSC군 > NAC군순으로 높았다. 3) 소장의 무게는 UFC군이 NAC군에 비해 유의하게 높았으며, 소장의 길이는 각 실험군에서 유의적인 차이가 없었으며 맹장의 무게 및 장통과 시간도 유의적인 차이가 없었다. 4) 맹장내 단쇄지방산의 함량은 NSC군이 UFC군이나 NAC군에 비해 유의하게 높아 장내 미생물에 의한 발효가 활성화되고 있었으며 장내 Bifidobacterium 증식도 NSC군이 다른 군에 비해 활발하였다. 5) 소장세포의 증식은 NSC군에서 낮았다. 이상의 결과로 볼때 nano-scale로 입자의 크기가 감소된 옥수수 전분은 소화흡수율을 증가시켜 성장능력을 증진하는 것으로 나타났으며, Bifidobacterium 증식 촉진, 단쇄 지방산 생성을 촉진하는 효과를 갖고 있어 상대적인 영양밀도를 높이는 기능성을 갖고 있는 것으로 나타났다. 따라서 장기능이 미숙한 유아기, 장기능이 불완전하거나 미약한 환자, 노인등의 특수목적 영양식의 기본재료로 활용될 수 있음을 제안한다.

• 대한전자공학회논문지SD
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• 제38권2호
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• pp.95-102
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• 2001

Nano-scale의 게이트 길이를 가지는 MOSFET소자는 접합 깊이가 20∼30㎚정도로 매우 얕은 소스/드레인 확장 영역을 필요로 한다. 본 연구에서는 As₂/sup +/ 이온의 10keV이하의 낮은 에너지 이온 주입과 RTA(rapid thermal annealing)공정을 적용하여 20㎚이하의 얕은 접합 깊이와 1.O㏀/□ 이하의 낮은 면저항 값을 가지는 n/sup +/-p접합을 구현 하였다. 이렇게 형성된 n/sup +/-p 접합을 nano-scale MOSFET소자 제작에 적용 시켜서 70㎚의 게이트 길이를 가지는 NMOSFET을 제작하였다. 소스/드레인 확장 영역을 As₂/sup +/ 5keV의 이온 주입으로 형성한 100㎚의 게이트 길이를 가지는 NMOSFET의 경우, 60mV의 낮은 V/sub T/(문턱 전압감소) 와 87.2㎷의 DIBL (drain induced barrier lowering) 특성을 확인하였다. 10/sup 20/㎝/sup -3/이상의 도핑 농도를 가진 abrupt한 20㎚급의 얕은 접합, 그리고 이러한 접합이 적용된 NMOSFET소자의 전기적 특성들은 As₂/sup +/의 낮은 에너지의 이온 주입 기술이 nano-scale NMOSFET소자 제작에 적용될 수 있다는 것을 제시한다.

• Advances in nano research
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• 제8권4호
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• pp.283-292
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• 2020

In the present research, differential quadrature (DQ) method has been utilized for investigating free vibrations of porous functionally graded (FG) micro/nano beams in thermal environments. The exact location of neutral axis in FG material has been assumed where the material properties are described via porosity-dependent power-law functions. A scale factor related to couple stresses has been employed for describing size effect. The formulation of scale-dependent beam has been presented based upon a refined beam theory needless of shear correction factors. The governing equations and the associated boundary conditions have been established via Hamilton's rule and then they are solved implementing DQ method. Several graphs are provided which emphasis on the role of porosity dispersion type, porosity volume, temperature variation, scale factor and FG material index on free vibrational behavior of small scale beams.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2009년도 추계학술대회 논문집
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• pp.32-32
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• 2009

Silicon carbide (SiC) is a wide-bandgap semiconductor that has materials properties necessary for the high-power, high-frequency, high-temperature, and radiation-hard condition applications, where silicon devices cannot perform. SiC is also the only compound semiconductor material. on which a silicon oxide layer can be thermally grown, and therefore may fabrication processes used in Si-based technology can be adapted to SiC. So far, atomic force microscopy (AFM) has been extensively used to study the surface charges, dielectric constants and electrical potential distribution as well as topography in silicon-based device structures, whereas it has rarely been applied to SiC-based structures. In this work, we investigated that the local oxide growth on SiC under various conditions and demonstrated that an increased (up to ~100 nN) tip loading force (LF) on highly-doped SiC can lead a direct oxide growth (up to few tens of nm) on 4H-SiC. In addition, the surface potential and topography distributions of nano-scale patterned structures on SiC were measured at a nanometer-scale resolution using a scanning kelvin probe force microscopy (SKPM) with a non-contact mode AFM. The measured results were calibrated using a Pt-coated tip. It is assumed that the atomically resolved surface potential difference does not originate from the intrinsic work function of the materials but reflects the local electron density on the surface. It was found that the work function of the nano-scale patterned on SiC was higher than that of original SiC surface. The results confirm the concept of the work function and the barrier heights of oxide structures/SiC structures.

• KSTLE International Journal
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• 제5권2호
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• pp.37-43
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• 2004

Abstract : Nano/micro-scale friction properties were investigated on Si (100) and three self-assembled monolayers (SAMs) (PFOTC, DMDM, DPDM) coated on Si-wafer by chemical vapor deposition technique. Experiments were conducted at ambient temperature(24$pm$1$circ$C) and humidity(45$pm$5%). Friction at nano-scale was measured using Atomic Force Microscopy (AFM) in the range of 0-40nN normal loads. In both Si-wafer and SAMs, friction increased linearly as a function of applied normal load. Results showed that friction was affected by the inherent adhesion in Ssi-wafer, and in the case of SAMs the physical/chemical structures had a major influence. Coefficient of friction of these test samples at the micro-scale was also energies. In order to study the effect of contact area on coefficient of friction at the micro-scale, friction was measured for Si-wafer and DPDM against Soda Lime balls (Duke Scientiffic Corporation) of different radii (0.25 mm, 0.5 mm and 1 mm) at different applied normal loads (1500, 3000 and 4800 mN). Results showed that Si-wafer had higher coefficient of friction than DPDM. Further, unlike that in the case of DPDM, friction in Si-wafer was severely influenced by its wear. SEM evidences showed that solid-solid adhesion was the wear mechanism in Si-wafer.

• KSTLE International Journal
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• 제6권1호
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• pp.13-16
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• 2005

Friction characteristics at nano-scale of self-assembled monolayers (SAMs) having different chain lengths and end groups were experimentally studied.51 order to understand the effect of the chain length and end group on the nano-scalefriction: (1) two different SAMs of shorter chain lengths with different end groups such as methyl and phenyl groups, and (2)four different kinds of SAMs having long chain lengths (C10) with end groups of fluorine and hydrogen were coated on siliconwafer (100) by dipping method and Chemical Vapour Deposition (CVD) technique. Their nano-scale friction was measuredusing an Atomic Force Microscopy (AFM) in the range of 0-40 nN normal loads. Measurements were conducted at the scanning speed of 2 $mu$m/s for the scan size of 1$mu$m x 1 $mu$m using a contact mode type $Si_3N_4$ tip (NPS 20) that had a nominal spring constant0.58 N/m. All experiments were conducted at anlbient temperature (24 $pm$1$circ$C) and relative humidity (45 $pm$ 5%). Results showedthat the friction force increased with applied normal load for all samples, and that the silicon wafer exhibited highest frictionwhen compared to SAMs. While friction was affected by the inherent adhesion in silicon wafer, it was influenced by the chainlength and end group in the SAMs. It was observed that the nano-friction decreased with the chain length in SAMs. In the caseof monolayers with shorter length, the one with the phenyl group exhibited higher friction owing to the presence of benBenerings that are stiffer in nature. In the case of SAMs with longer chain length, those with fluorine showed friction values relativelyhigher than those of hydrogen. The increase in friction due to the presence of fluorine group has been discussed with respect tothe siBe of the fluorine atom.

• 전기학회논문지
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• 제57권10호
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• pp.1876-1882
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• 2008

Nano manipulator is used to manufacture Carbon NanoTube(CNT) tips. Using nano manipulator, operator attaches a CNT at the apex of Atomic Force Microscope(AFM) tip, which requires a mastery of mechanics and long manufacture time. Nano manipulator is installed inside a Scanning Electron Microscope(SEM) chamber to observe the operation. This paper presents a control scheme for horizontal axes of nano manipulator via processing SEM image. Edges of AFM tip and CNT are first detected, and the position information so obtained is fed to control horizontal axes of nano manipulator. That is, a visual servoing loop is realized to control the axes more precisely in nano scale.