• 제목/요약/키워드: SURFACE MORPHOLOGY

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탄산 에틸렌계 용액 중에서 생성되는 흑연 음극 표면피막의 형상 및 저항에 미치는 충방전 속도의 영향 (Effects of Charge-discharge Rate on Morphology and Resistance of Surface Film on a Graphite Negative Electrode in an Ethylene Carbonate-based Solution)

  • 정순기;김보겸
    • 한국수소및신에너지학회논문집
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    • 제24권2호
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    • pp.179-185
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    • 2013
  • The behavior of surface film formation was greatly dependent on the speed of potential cycling. In $LiClO_4$ / EC + DEC, cyclic voltammetry results showed that the peaks originated from surface film formation on graphite electrode at the high charge-discharge rate was shifted to the lower potentials as the charge-discharge rate decrease. This indicates that surface films with different morphology and thickness were formed by different charge-discharge rate. Transmission electron microscopy (TEM) results indicated that the properties such as thickness and morphology of the surface film were greatly affected by the charge-discharge rate. Electrochemical impedance spectroscopy (EIS) showed that the resistance of surface film was affected by the speed of potential cycling. In addition, the charge transfer resistance was also dependent on the charge-discharge rate indicating that the charge transfer reaction was affected by the nature of surface film. TEM and EIS results suggested that the chemical property as well as the physical property of the surface film was affected by the charge-discharge rate.

Nanotube Morphology Control of Ti-30Nb-xTa Alloys by Applied Voltages

  • Kim, Eun-Sil;Choe, Han-Cheol
    • 한국표면공학회:학술대회논문집
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    • 한국표면공학회 2013년도 춘계학술대회 논문집
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    • pp.78-78
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    • 2013
  • This study has investigated the nanotube morphology control of Ti-30Nb-xTa alloys by applied voltages. The morphology changed from small diameter to large diameter with increasing applied voltage, whereas, changed from large diameter to small diameter with decreasing applied voltage.

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Photoluminescence property of vertically aligned ZnO nanorods.

  • Das, S.N.;Kar, J.P.;Choi, J.H.;Myoung, J.M.
    • 한국재료학회:학술대회논문집
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    • 한국재료학회 2009년도 추계학술발표대회
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    • pp.25.2-25.2
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    • 2009
  • Vertically aligned zinc oxide(ZnO) nanorods (NRs) with different surface morphology were grown by metal organic chemical vapor deposition (MOCVD) on sapphire substrate with different deposition condition. Based on the surface morphology, ZnO nanostructures are divided into three types: nanoneedles, nanonails and nanorods with rounded tip. Variable temperature photoluminescence (PL) have employed to probe the exciton recombination in high density and vertically aligned ZnO Nanorod arrays. Low temperature photoluminescence measurements do not show any significant yellow emission, but the near band edge excitonic emission shows very strong dependence with the surface morphology. The recombination properties are expected to be different due to different surface-to-volume ratio and distribution of potential fluctuations of intrinsic defects.

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선형배율보정을 통한 DFF 기반의 삼차원 형상 측정법 (A Measurement Method of Three-Dimensional Surface Morphology Based on Depth-from-Focus through Linear Magnification Calibration)

  • 김경범;신영수
    • 한국정밀공학회지
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    • 제22권9호
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    • pp.115-122
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    • 2005
  • Errors resulting from magnification variations of a optical system are largely generated in three-dimensional shape measurements based on depth-from-focus. In the case of measuring the surface morphology of tiny objects based on DFF, images are acquired with a very small interval so that magnification changes can be minimized. However, the magnification variations are actually existed in the acquired images and so focus measures are wrongly or ambiguously extracted. In this paper, a methodology with linear magnification calibrations, based on DFF, is proposed to make more accurate measurement in surface morphology with high depth discontinuity, compared with previous ones. Several experiments show that the proposed method outperforms existing ones without magnification calibrations.

정전기 분무 증착법에 대한 최근 연구 동향 고찰 (Research Issues of Electrostatic Spray Deposition (ESD) Technique)

  • 류성욱;이상용
    • 한국분무공학회지
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    • 제11권1호
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    • pp.7-16
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    • 2006
  • Performance of thin films fabricated with the electrostatic spray deposition (ESD) technique is strongly governed by surface morphology, which depends on deposition parameters such as deposition time and temperature, solution properties, and surface characteristics of substrates. In this article, the state of the art on the relationships between the surface morphology and the deposition parameters is presented. Also studies on the electro-hydrodynamic atomization process and the motion of drops relevant to the ESD technique are briefly reviewed, and the future research works are suggested.

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고분자 Langmuir 박막의 표면형상 (The Surface Morphology of Polymer Langmuir Film)

  • 정치섭
    • 한국전기전자재료학회논문지
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    • 제18권1호
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    • pp.81-88
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    • 2005
  • The Langmuir monolayers of polyamic acid salts with three kinds of alkyl chains have been investigated by means of conventional $\pi$-A isotherms and second harmonic generation measurements proposed in this paper. The surface molecular density dependence of second harmonic intensity clearly shows the region of aggregation while corresponding $\pi$-A isotherm doesn't show any changes in the surface morphology at the same region. The surface morphology analysis based on the second harmonic measurement was consistent with the Brewster angle microscope measurement results.

Kr가스에 의한 OLED용 Al 음전극의 표면 형상 (Surface morphology of Al cathode for OLED with Kr gas)

  • 김현웅;금민종;김경환
    • 한국전기전자재료학회:학술대회논문집
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    • 한국전기전자재료학회 2005년도 추계학술대회 논문집 Vol.18
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    • pp.283-284
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    • 2005
  • Al electrode for OLED was deposited by Facing Targets Sputtering(FTS) system which can reduce the damage of organic layer. The Al thin films were deposited on the slide glass as a function of working gas such as Ar, Kr or mixed gas. The film surface image was observed by AFM and SEM. In the results, when Al thin film were deposited using mixed gas, the surface morphology was improved in some region.

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Enhancement of the Surface Smoothness of Cu Ribbon for Solar Cell Modules

  • Cho, Tae-Sik;Cho, Chul-Sik
    • Transactions on Electrical and Electronic Materials
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    • 제16권1호
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    • pp.20-24
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    • 2015
  • We studied the relationship between the surface smoothness of the internal Cu ribbon and the morphology of the Sn-Pb plating layer for solar cell modules. A bumpy surface was observed on the surface of the solar ribbon, which caused irregular reflection of light. Large, Pb-rich, primary ${\alpha}$-phases were found below the convex surface of the solar ribbon, passing from the surface of the internal Cu ribbon to the surface of the plating layer. The primary ${\alpha}$-phases heterogeneously nucleated on the convex surface of the Cu ribbon, and then largely grew to the convex surface of the plating layer. The restriction of the primary ${\alpha}$-phase's formation was enabled by enhancing the smoothness of the Cu ribbon's surface; it was also possible to increase the adhesive strength and decrease contact resistance. We confirmed that the solar ribbon's surface smoothness depends on the internal Cu ribbon's surface smoothness.

NYAB 결정육성시 종자정의 방향이 성장외형 및 표면형상에 미치는 영향 (The Effect of Seed Orientation on Growth Form and Surface Morphology in Growing NYAB Crystal)

  • 정선태;최덕용
    • 한국결정학회지
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    • 제5권2호
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    • pp.93-99
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    • 1994
  • K2O/3MOOS/0.SBB03 융제를 사용하여 TSSG 법으로 육성한 Md:Yal3(BO3)4 (NYAB) 단결정의 결정외형 및 표면형상을 연구하였다. <100>과 <120> 종자정을 사용한 경우는 서로 다른 크기의 프리즘 면들과 (101) 면들이 발달하였고 <001> 종자정을 사용하였을 때는 (001) 면이 함께 발달하였다. 종자정의 방향이 <100>또는 <120> 일때 프리즘 면 위에 성장구룽이 많이 형성되었으나, <001> 일때는 이웃하는 (101) 면에 평행한 줄무늬가 형성 되었다. (101) 면은 이차원 핵생성에 의한 성장이 지배적이고, <001> 종지정을 사용할 때 발달하는 (001) 면은 나선형 전위에 의한 성장이 지배적이었다. 종자정의 방향은 성장외형을 변화시키고 성장외형과 결정의 질을 결정하는 중요한 성장변수로 작용하였다.

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