• 제목/요약/키워드: Metallic glass

검색결과 246건 처리시간 0.051초

OLED 디스플레이 제작을 위한 Joule 유도 결정화 공정에서의 유리기판에 대한 열해석 (Thermal Analysis on Glass Backplane of OLED Displays During Joule Induced Crystallization Process)

  • 김동현;박승호;홍원의;정장균;노재상;이성혁
    • 대한기계학회논문집B
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    • 제33권10호
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    • pp.797-802
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    • 2009
  • Large area crystallization of amorphous silicon thin-films on glass substrates is one of key technologies in manufacturing flat displays. Among various crystallization technologies, the Joule induced crystallization (JIC) is considered as the highly promising one in the OLED fabrication industries, since the amorphous silicon films on the glass can be crystallized within tens of microseconds, minimizing the thermally and structurally harmful influence on the glass. In the JIC process the metallic layers can be utilized to heat up the amorphous silicon thin films beyond the melting temperatures of silicon and can be fabricated as electrodes in OLED devices during the subsequent processes. This numerical study investigates the heating mechanisms during the JIC process and estimates the deformation of the glass substrate. Based on the thermal analysis, we can understand the temporal and spatial temperature fields of the backplane and its warping phenomena.

시효조건에 다른 $Fe_{78}B_{13}Si_9$ 비정질 합금의 결정화 연구 (The Effects of Aging Conditions on the Crystallization of $Fe_{78}B_{13}Si_9$ Metallic Glass)

  • 이원재;김기욱;민복기;송재성;홍진완;강원구;김윤동
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 1989년도 하계종합학술대회 논문집
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    • pp.291-294
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    • 1989
  • The effect of isothermal aging on the crystallization of $Fe_{78}B_{13}Si_9$ metallic glass has been investigated by electrical resistivity, X-ray measurements, bending test, thermal analysis and transmission electron microscpy. Amouphous $Fe_{78}B_{13}Si_9$ alloy was annealed isothermally for 5 to 1200 min. between $300^{\circ}C$ and $540^{\circ}C$. It has been found that close relation between relative resistivity and X-ray diffraction pattern showed. The crystalline peaks of ${\alpha}$-(Fe, Si) and $Fe_2B$ are detected by X-ray experiment. The crystalline phases observed by TEH show ${\alpha}$-(Fe, Si) and $Fe_2B$ with dendritic and cylindrical morphology, respectively. It has been also found that the embrittleness of aged samples rapidly increased with the crystallization and was shown before the crystallization.

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벌크비정질합금의 액상 성형성 평가 (Evaluation on Liquid Formability of Bulk Amorphous Alloys)

  • 주혜숙;강복현;김기영
    • 한국주조공학회지
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    • 제26권5호
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    • pp.227-231
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    • 2006
  • Liquid formability of bulk amorphous alloys is known to be very poor due to their high viscosity comparing with conventional metallic materials. It is important to have the fabricating technology of bulk amorphous alloys in order to make the components with complicated shape. Liquid formability includes the mold cavity filling ability and the hot tear(crack) resistance during solidification. A mold made of a commercial tool steel for the formability test was designed. Melting was performed by the arc melting furnace with melting capacity of 200 g in an argon atmosphere. Liquid formability and glass forming ability of Cu base and Ni base bulk amorphous alloys were measured and evaluated. Mold filling ability of Ni-Zr-Ti-Si-Sn alloy was better than that of Cu-Ni-Zr-Ti alloy, however the reverse is the hot tear resistance. Bulk amorphous alloy is very susceptible to crack if partial crystallization occurs during solidification. Crack resistance was thought to be closely related with the glass forming ability.

대기 플라즈마 용사공정을 이용한 Cu계 벌크 비정질 금속 코팅의 미세조직 분석과 나노 압입시험을 이용한 상 분석 (Microstructure Evolution of Cu-based BMG Coating during APS Process and Phase Analysis by Nano-indentation Test)

  • 김정환;강기철;윤상훈;나현택;이창희
    • Journal of Welding and Joining
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    • 제27권6호
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    • pp.43-48
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    • 2009
  • In this study, Cu-based bulk metallic glass (BMG) coatings were deposited by atmospheric plasma spraying (APS) process with different process conditions (with- and without hydrogen gas). As adding the hydrogen gas, thermal energy in the plasma flame increased and induced difference in the melting state of the Cu-based BMG particles. The microstructure and mechanical properties of the coatings were analyzed using a scanning electron microscope (SEM) with an energy dispersive spectroscopy (EDS) and nano-indentation tester in the light of phase analysis. It was elucidated by the nano-indentation tests that un-melted region was a mainly amorphous phase which showed discrete plasticity observed as the flow serrations on the load.displacement (P - h) curves, and the curves of solidified region showed lower flow serrations as amorphous phase mingled with crystalline phase. Oxides produced during the spraying process had the highest hardness value among the phases and were well mixed with other phases resulted from the increase in melting degree.

접착층을 고려한 플라즈모닉 금 나노 디스크의 광산란 특성 (Effect of Adhesion layer on the Optical Scattering Properties of Plasmonic Au Nanodisc)

  • 김주영;조규만;이경석
    • 대한금속재료학회지
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    • 제46권7호
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    • pp.464-470
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    • 2008
  • Metallic nanostructures have great potential for bio-chemical sensor applications due to the excitation of localized surface plasmon and its sensitive response to environmental change. Unlike the commonly explored absorption-based sensing, the optical scattering provides single particle detection scheme. For the localized surface plasmon resonance spectroscopy, the metallic nanostructures with controlled shape and size have been usually fabricated on adhesion-layer pre-coated transparent glass substrates. In this study, we calculated the optical scattering properties of plasmonic Au nanodisc using a discrete dipole approximation method and analyzed the effect of adhesion layer on them. Our result also indicates that there is a trade-off between the surface plasmon damping and the capability of supporting nanostructures in determining the optimal thickness of adhesion layer. Marginal thickness of Ti adhesion layer for supporting Au nanostructures fabricated on a silica glass substrate was experimentally analyzed by an adhesion strength test using a nano-indentation technique.