• 제목/요약/키워드: Beam-Forming

검색결과 351건 처리시간 0.027초

이온빔 스퍼터링에 의한 ATO 박막의 실온 증착 및 열처리에 따른 특성변화 (Room Temperature Deposition and Heat Treatment Behavior of ATO Thin Films by Ion Beam Sputtering)

  • 구창영;김경중;김광호;이희영
    • 한국세라믹학회지
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    • 제37권11호
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    • pp.1025-1032
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    • 2000
  • 산화분위기에서의 반응성 이온빔 스퍼터링법으로 Sn과 Sb 금속 타겟을 사용하여 실온에서 ATO 박막을 증착하였다. Sb 첨가량, 박막의 두께 및 열처리가 ATO 박막의 전기적 특성과 광학적 특성에 미치는 효과를 연구하고자 하였다. 제조된 ATO 박막의 두께는 약 1500$\AA$과 1000$\AA$으로 조절하였으며, Sb 농도는 10.8wt% 또는 14.9wt%임이 XPS 분석에 의하여 확인되었다. 증착한 박막의 열처리는 40$0^{\circ}C$~$600^{\circ}C$의 온도범위에서 산소 또는 forming gas(10% H$_2$-90% Ar) 분위기에서 30분간 수행하였다. 이렇게 제조된 ATO 박막은 Sb의 첨가량, 두께 및 열처리 조건에 따라 다양한 전기 비저항 값과 가시광선 대역에서의 광투과도를 나타내었다.

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정전기력을 이용한 마이크로 액츄에이터 소지의 미소 기계적 구동특성 분석 (Analysis of Micromechanical Characteristics of Microactuator Materials Using the Electrostatic Force)

  • 이세호;김재석;손동일;박유근;권동일
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 1999년도 하계학술대회 논문집 G
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    • pp.3286-3288
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    • 1999
  • The electrostatically actuated test structure was presented to measure the micro mechanical characteristics of micromaterials as thin films forming the microactuators. The test structure was fabricated by the surface micromachining processes and driven by the electrostatic force, In order to measure the fracture toughness, the sharp notch in the test structure was introduced by the etching process. On the basis of the beam bending theory, the elastic modulus was measured by using the microcantilevr beam and the mechanical displacement, curvature and deflection curve under the electrostatic force was evaluated by using the electrostatic structure.

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Failure Paths Analyses of the Leadframe/EMC System

  • Lee, H.Y.;Kim, S.R.
    • 마이크로전자및패키징학회지
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    • 제7권2호
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    • pp.7-12
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    • 2000
  • Copper-based leadframe sheets were oxidized in a black-oxide forming solution, and molded with epoxy molding compound (EMC) to form sandwiched double-cantilever beam (SDCB) specimens. The adhesion strength of leadframe/EMC interface was measured in terms of fracture toughness by using SDCB specimens and the fracture surfaces were analyzed by various equipments such as glancing-angle XRD, AFM, and SEM. Results showed that three types of failure paths, which were closely related to the surface condition of leadframes before molding.

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중성자 조사용 전기도체의 첨가물 효과 (Effect of Metal Oxide of Ceramic Superconductor for Neutron beam Irradiation)

  • 이상헌;최용
    • 전기학회논문지
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    • 제57권3호
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    • pp.429-432
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    • 2008
  • Much studies have been concentrated to develop the fabrication technique for high critical current density but still there are a lot of gap which should be overcome for large scale application of superconducting materials at liquid nitrogen temperature. The improvement of the critical current can be achieved by forming the nano size defect working as a flux pinning center inside the superconductor. In this paper, the establishment of fabrication condition and additive effects of second elements were examined so as to improve the related properties to the practical use of superconductor.

Discharge characteristics of MgO layer prepared via aqueous solution process

  • Choi, Hak-Nyun;Kim, Yong-Seog
    • 한국정보디스플레이학회:학술대회논문집
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    • 한국정보디스플레이학회 2006년도 6th International Meeting on Information Display
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    • pp.379-382
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    • 2006
  • In this study, an attempt was made to form magnesium oxide layer via aqueous solution route of salt precipitation process. A layer with flake morphology was formed from the process and various dopants were added during the forming process. The films formed were characterized using SEM, XRD, and cathodoluminescence measurement. In addition, the discharge characteristics were evaluated using panel tests. The results indicate that MgO film can be formed via the aqueous solution process successfully, of which characteristics are comparable to those of MgO film formed by e-beam evaporation process.

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아연도금강판에 대한 레이저 용접부의 성형성 (Formability of Laser Welds in Zn-coated Steel Sheets)

  • 박찬철
    • 한국정밀공학회:학술대회논문집
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    • 한국정밀공학회 1996년도 춘계학술대회 논문집
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    • pp.176-180
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    • 1996
  • Continuous wave CO$_{2}$laser beam welding and formability of zinc coated steel shets were investigated. First, optimal welding condition could be obtained in but welding by using the data for heat input and welding velocity. The highest value of Erichsen test is 79.3% compare to that of base matel. Secondly, Formability of laser welds was investigated by using ball punch tester. Finally, the forming results of butt-welded sheets showed that the joing design was important to apply the laser welded blank in the automotive production.

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가상안테나를 이용한 스마트 안테나의 성능개선 (Improvement of Smart Antenna System Performance Using virtual antennas)

  • 임채현;문성훈;한동석
    • 대한전자공학회:학술대회논문집
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    • 대한전자공학회 2001년도 하계종합학술대회 논문집(1)
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    • pp.49-52
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    • 2001
  • A virtual antenna system is presented to increase the channel capacity of a smart antenna in cdma2000. Although a smart antenna system can increase channel capacity by forming a beam to a desired user direction, an increase of channel capacity is limited by the number of antenna elements. A virtual antenna is proposed to improve the channel capacity by increasing the degree of freedom. The results show that the proposed system has a larger channel capacity than a conventional smart antenna system for the same number of antenna elements.

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아연도금강판에 대한 레이저 용접부의 성형성 (Formability of Laser Welds in Zn-coated Steel Sheets)

  • 박찬철;김재도
    • 대한용접접합학회:학술대회논문집
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    • 대한용접접합학회 1996년도 특별강연 및 춘계학술발표 개요집
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    • pp.46-50
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    • 1996
  • Continuous wave $CO_2$ laser beam welding and formability of zinc coated steel sheets were investigated. First, optimal welding condition could be obtained in butt welding by using the data for heat input and welding velocity. The highest value of Erichsen test is 79.3% compare to that of base metal. Secondly, Formability of laser welds was investigated by using ball punch tester. Finally, the forming results of butt-welded sheets showed that the joining design was important to apply the laser welded blank in the automotive production.

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Recent advances in excimer-laser-based crystallization for active-matrix displays

  • Turk, Brandon A.;Herbst, Ludolf;Simon, Frank;Paetzel, Rainer
    • 한국정보디스플레이학회:학술대회논문집
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    • 한국정보디스플레이학회 2007년도 7th International Meeting on Information Display 제7권1호
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    • pp.12-15
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    • 2007
  • Excimer-laser-based crystallization is ideallysuited for forming crystalline Si films on glass substrates for use in active-matrix displays. In this paper, we will report on recent and significant technical advances in light sources and beam delivery systems targeted at enabling ultra-uniform mura-free low-temperature polycrystalline silicon active-matrix backplanes while simultaneously lowering production costs and increasing throughput.

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Digital Beamforming(DBF) 안테나 기술 동향 (The Trends of Digital Beamforming Antenna Technology)

  • 배창호
    • 전자통신동향분석
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    • 제21권2호통권98호
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    • pp.200-209
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    • 2006
  • 가입자의 수가 놀라운 비율로 증가하고 고품질. 광대역 데이터 통신에 대한 요구가 증가하면서 이동 통신에 사용되는 주파수원이 부족하게 될 것으로 예상된다. 주파수의 재사용률을 향상시키기 위하여 공간적인 방향성을 가지는 안테나를 이용하는 것과 송신하는 전력을 줄이는 것은 주파수원의 효율적인 사용을 할 수 있게 할 것이다. 가까운 미래에는 도달하는 신호를 빨리 추적하는 높은 이득을 가지는 안테나가 많이 요구될것이고 빠르게 성장할 것으로 기대된다. 그런 다양한 기능을 가지는 안테나를 실현하기 위하여 디지털 빔 형성 안테나가 미래의 지능 안테나로 제안되었다[1], [2]. 따라서 본 논문에서는 디지털 빔 형성(digital beam forming, 이하 DBF라 한다.) 안테나의 빔형성 방법, 원리, 특징에 대하여 살펴볼 것이다.