• 제목/요약/키워드: UNI

검색결과 1,612건 처리시간 0.037초

RF 마그네트론 스퍼터링을 이용한 FBAR 소자용 ZnO 박막의 특성 (Characteristics of ZnO thin films by RF magnetron sputtering for FBAR application)

  • 김선영;이능헌;김수길;박성현;정민곤;신영화;지승한;이덕출
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 2003년도 하계학술대회 논문집 C
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    • pp.1523-1525
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    • 2003
  • Due to the rapid development of wireless networking system, researches on the communication devices are mainly focus on microwave frequency devices such as filters, resonators, and phase shifters. Among them, Film bulk acoustic resonator (FBAR) has been paid extensive attentions for their high performance. In this research, ZnO thin films were deposited by RF-magnetron sputtering on Al/$SiO_2$/Si wafer and then crystalline properties and surface morphology were examined. To measure crystalline structure and surface morphology X-ray diffraction (XRD) and Scanning Electron Microscope (SEM) were employed. It was showed that crystalline properties of ZnO thin films were strongly dependant on the deposition conditions. As increasing the deposition temperature and the deposition pressures, the peak intensities of ZnO(002) plane were increased until $300^{\circ}C$, then decreased rapidly. At the sputtering conditions of RF power of 213 W and working pressure of 15 m Torr, ZnO film had excellent c-axis orientation, surface morphology, and adhesion to the substrate. In conclusion we optimized smooth surface with very small grains as well as highly c-axis oriented ZnO film for FBAR applications.

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ITU-T와 ATM Forum의 B-ISDN 점대점 호/연결 신호 기능 상호 운용 방안 (Interoperability Schemes for the B-ISDN Pint-to-point Call/Connection Signalling of ITU-T and ATM Forum)

  • 김석배;민병도;박남훈;이석기
    • 한국정보처리학회논문지
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    • 제4권10호
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    • pp.2512-2520
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    • 1997
  • B-ISDN 사용자 망 접면에서 호/연결 제어를 위한 신호 기능은 ITU-T의 Q.2931과 ATM Forum의 UNI 3.1이 대표적이다. 점대점 호/연결 제어 절차를 제공하는 Q.2931은 공중망을 구성하는 장치에 적용이 되며, ATM Forum의 UNI 3.1은 여러 가지의 단말 장치 위주의 ATM 사설망을 구성하는데 적용된다. 국내의 B-ISDN 개발 사업에서는 방 장치인 ATM소형 교환기, B-NT 등과 단말장치인 B-TA등을 개발하였다. 그러나 B-ISDN에서 다양한 서비스를 제공하기 위해서는 여러 종류의 단말장치들을 필요로 한다. 공중망에서 UNI 3.1 단말 장치를 수용할 수 있다면, 여러 종류의 단말장치들을 확보할 수 있으므로 매우 효율적이다. 그러므로, 본 논문에서는 B-ISDN 공중망에 UNI 3.1 단말 장치를 접속하여 점대점 신호 절차 수행 시에 발생할 수 있는 문제점들을 예측하고, 호/연결이 원만하게 진행될 수 있는 방안들을 제안한다.

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Hgl2의 누설전류 저감을 위한 다층구조 제작 및 특성 평가 (The Multi-layer Fabrication and Characteristic Performance for Dark Current Reduction of Mercury Iodide)

  • 김경진;박지군;강상식;차병열;조성호;김진영;문치웅;남상희
    • 한국전기전자재료학회:학술대회논문집
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    • 한국전기전자재료학회 2005년도 하계학술대회 논문집 Vol.6
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    • pp.388-389
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    • 2005
  • In this paper, the electric properties of mercury Iodide multi-layer samples has been investigated. We measured and analyzed their performance parameters such as the X-ray sensitivity and dark-current for a mercury Iodide multi-layer X-ray detector with a dielectric layer. The digital X-ray image detector can be constructed by integrating photoconduction multi-layer that dielectric layer has characteristics of low dark-current, high X-ray sensitivity. However this process has found to have complexity on the performance of the sample. We have investigate dielectric layer that it substitute dielectric layer for HgO(Mercury Oxide). We have employed two approaches for producing the mercury Iodide sample : 1) Physical Vapor Deposition(PVD) and 2) Particle-In-Binder(PIB). In this paper fabricated by PIB Method with thicknesses ranging from approximately 180um to 240um and we could produce high-quality samples for each technique particular application. As results, the dielectric materials such as HgO between the dielectric layer and the top electrode may reduce the dark-current of the samples. Mercury Iodide multi-layer having HgO has characteristics of low dark-current, high X-ray sensitivity and simple processing. So we can acquired a enhanced signal to noise ratio. In this paper offer the method can reduce the dark-current in the X-ray detector.

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RF 스퍼터링법에 의한 SBT 커패시터의 열처리 시간 특성 (Annealing Time Properties of SBT Capacitors by RF Sputtering method)

  • 조춘남;오용철;김진사;신철기;이동규;최운식;이성일;이준웅
    • 한국전기전자재료학회:학술대회논문집
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    • 한국전기전자재료학회 2004년도 하계학술대회 논문집 Vol.5 No.2
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    • pp.817-820
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    • 2004
  • The $Sr_{0.7}Bi_{2.6}Ta_2O_9$(SBT) thin films are deposited on Pt-coated electrode($Pt/TiO_2/SiO_2/Si$) using a RF magnetron sputtering method. The ferroelectric properties of SBT capacitors with annealing time were studied. In the SEM images, Bi-layered perovskite phase was crystallized at 10min and grains largely grew with annealing tune. SBT thin films are transformed from initial amorphous phase to the fully formed layer-structured perovskite. During the annealing process at $750^{\circ}C$, we found that an fluorite-like stage is formed after 3min. In the XRD pattern, the SBT thin films after 3min annealing time had (105) orientation. The ferroelectric properties of SBT capacitor with annealing time represent a favorable properties at 60 min. The maximum remanent polarization and the coercive electric field with 60 min are $12.40C/cm^2$ and 30kV/cm, respectively. The leakage current density with 60min is $6.81{\times}10^{-10}A/cm^2$.

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와전류형 브레이크의 특성해석 (Analysis of Eddy Current Brake system)

  • 장석명;차상도;이성호;정상섭;이중호
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 2001년도 하계학술대회 논문집 B
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    • pp.889-891
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    • 2001
  • The eddy current brake system is one of important application of eddy current. It is adequate to obtain safe braking force in high speed transportation system and electric vehicle etc. There is a variety of configurations and materials used in manufacturing of eddy current brakes. This paper proposes the eddy current brakes which uses permanent magnet. The dynamic characteristic has been analyzed to FEM and compared with measured data.

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Y211 기판 위의 Bi-2212 후막의 후열처리 특성 (Annealing Characteristic of Bi-2212 thick Films on Y2l1 substrate)

  • 강형곤;임성훈;정동철;임성우;한병성
    • 한국초전도학회:학술대회논문집
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    • 한국초전도학회 1999년도 High Temperature Superconductivity Vol.IX
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    • pp.296-299
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    • 1999
  • Bi$_2Sr_2CaCu_2O$(Bi-2212) thick films were fabricated on Y2l1 substrate by screen printing method. And the samples were annealed in various atmospheres, respectively. Though samples had many voids, the sample annealed in N$_2$ ; O$_2$ = 1:0 atmosphere and the sample in N$_2$ : O$_2$ = 0:1 showed some Bi 2212 low phase in comparison to other samples. The thickness of Bi-2212 on Y2ll substrates was about 20 ${\mu}$m.

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