• 제목/요약/키워드: Second hole

검색결과 211건 처리시간 0.027초

비전시스템을 이용한 이동물체 자동검사에 관한 연구 (A Study on Automatic Inspection Algorithm for Moving Object using by Vision System)

  • 조영석
    • 디지털산업정보학회논문지
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    • 제5권1호
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    • pp.99-105
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    • 2009
  • Recently the research is much interested in about the inspection system using by computer vision system. In this paper, we deal with shape inspection technique for moving to be long and narrow object on conveyor belt. first, we are acquired for moving object on conveyor belt. then the object segmentation is using by color information for background and object. the object position be calculated by horizontal and a vertical histogram. second, we are checked for two hole in front part, widths and top/bottom side information in middle part, and finally checking for two holes in rear part. The performance of our proposed model is evaluated by experiments, within error of 1㎜, and can be checking to 17 object /min.

Selective Growth of Carbon Nanotubes using Two-step Etch Scheme for Semiconductor Via Interconnects

  • Lee, Sun-Woo;Na, Sang-Yeob
    • Journal of Electrical Engineering and Technology
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    • 제6권2호
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    • pp.280-283
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    • 2011
  • In the present work, a new approach is proposed for via interconnects of semiconductor devices, where multi-wall carbon nanotubes (MWCNTs) are used instead of conventional metals. In order to implement a selective growth of carbon nanotubes (CNTs) for via interconnect, the buried catalyst method is selected which is the most compatible with semiconductor processes. The cobalt catalyst for CNT growth is pre-deposited before via hole patterning, and to achieve the via etch stop on the thin catalyst layer (ca. 3nm), a novel 2-step etch scheme is designed; the first step is a conventional oxide etch while the second step chemically etches the silicon nitride layer to lower the damage of the catalyst layer. The results show that the 2-step etch scheme is a feasible candidate for the realization of CNT interconnects in conventional semiconductor devices.

Fuzzy-based Field-programmable Gate Array Implementation of a Power Quality Enhancement Strategy for ac-ac Converters

  • Radhakrishnan, N.;Ramaswamy, M.
    • Journal of Electrical Engineering and Technology
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    • 제6권2호
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    • pp.233-238
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    • 2011
  • In the present work, a new approach is proposed for via interconnects of semiconductor devices, where multi-wall carbon nanotubes (MWCNTs) are used instead of conventional metals. In order to implement a selective growth of carbon nanotubes (CNTs) for via interconnect, the buried catalyst method is selected which is the most compatible with semiconductor processes. The cobalt catalyst for CNT growth is pre-deposited before via hole patterning, and to achieve the via etch stop on the thin catalyst layer (ca. 3nm), a novel 2-step etch scheme is designed; the first step is a conventional oxide etch while the second step chemically etches the silicon nitride layer to lower the damage of the catalyst layer. The results show that the 2-step etch scheme is a feasible candidate for the realization of CNT interconnects in conventional semiconductor devices.

Study of Electron Injection of Pentacene Field Effect Transistor with Au Electrodes by C-V and SHG Measurements

  • Lim, Eun-Ju;Manaka, Takaaki;Tamura, Ryosuke;Ohshima, Yuki;Iwamoto, Mitsumasa
    • Transactions on Electrical and Electronic Materials
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    • 제9권4호
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    • pp.151-155
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    • 2008
  • Using pentacene field effect transistors (FETs) with Au source and drain electrodes, electron injection from the Au electrodes into the pentacene was investigated. The capacitance-voltage (C-V) and optical second harmonic generation (SHG) measurements were employed. Electron injection from the Au electrodes was suggested by the hysteresis behavior with the C-V characteristics and slowly decaying SHG signal under DC biasing, A mechanism of hole-injection assisted by trapped electrons is proposed. To confirm electron injection process, light-emitting behavior under the application of AC applied voltage was observed.

T-stress solutions for cracks in rectangular plates with multiple holes

  • Yu, Jackie;Wang, Xin;Tan, Choon-Lai
    • Structural Engineering and Mechanics
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    • 제26권5호
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    • pp.557-568
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    • 2007
  • The elastic T-stress is increasingly being recognized as an important second parameter to the stress intensity factor for fracture and fatigue assessments. In this paper, the mutual or M-contour integral approach is employed in conjunction with the Boundary Element Method (BEM) to determine the numerical T-stress solutions for cracks in plates with multiple holes. The problems investigated include plates of infinite width with multiple holes at which single or double, symmetric cracks have grown from. Comparisons of these results are also made with the corresponding solutions of finite plates with a single hole. For completeness, stress intensity factor solutions for the cracked geometries analyzed are presented as well. These results will be useful for failure assessments using the two-parameter linear elastic fracture mechanics approach.

증착조건에 따른 undoped ZnO 박막의 특성 변화 (Property variations of undoped ZnO thin films with deposition conditions)

  • 남형진;이규항;조남인
    • 반도체디스플레이기술학회지
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    • 제7권3호
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    • pp.51-54
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    • 2008
  • In this study, we investigated variations in undoped ZnO thin film properties with working pressure, $O_2$/Ar ratio, and annealing ambient. Higher vacuum pressure during deposition was observed to bring about slower growth rate resulting in samples with better crystallinity as well as hole generation efficiency through formation of shallower oxygen interstitial. Given that $O_2$/Ar ratio is greater than unity, O provided from the ambient to ZnO during annealing was found to preferably situate at interstitial sites. When He was used for the second annealing, significant changes were not observed. On the other hand, O ambient caused increased density of oxygen interstitial, thereby making the film more intrinsic-like high resistivity ZnO.

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Nanostructuring of Semi-conducting Block Copolymers: Optimized Synthesis and Processing for Efficient Optoelectronic Devices

  • Hadziioannou, Georges
    • 한국고분자학회:학술대회논문집
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    • 한국고분자학회 2006년도 IUPAC International Symposium on Advanced Polymers for Emerging Technologies
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    • pp.74-75
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    • 2006
  • In organic opto-electronic applications, such as light emitting diodes (LEDs) and photovoltaic devices (PVDs), the morphology of the active layer is of crucial importance. To control the morphology of the active layer the self-assembling properties of block copolymers was used. Several rod-coil semiconducting diblock copolymers consisting of a conjugated block and a second coil block functionalized with electron transporting and/or accepting materials (such as $C_{60}$) were synthesized. The conjugated block acting as light absorbing, electron donating and hole transporting material. The donor/acceptor photovoltaic devices performance with active layer the above mentioned semiconducting block copolymers will be presented.

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Elementary Students' Perceptions of Earth Systems and Environmental Issues

  • Lee, Hyon-Yong;Fortner, Rosanne W.
    • 한국지구과학회지
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    • 제27권7호
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    • pp.705-714
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    • 2006
  • The purpose of this study was to explore the elementary students' perceptions of Earth systems and environmental issues. A survey was conducted to determine the students' perceptions on the following aveas: (1) the concepts of certainty and tangibility, (2) self-reported knowledge level, (3) perceived danger level of selected eight Earth systems and environmental issues, and (4) their primary information source on these issues. Results indicated that ozone hole, acid rain, El $Ni\widetilde{n}o$, and global warming were identified by the students as uncertain and intangible issues. Perceived certainty and perceived tangibility were highly positively correlated with self-reported knowledge compared to other relationships. The results also showed that learning from school was the most frequent information source for environmental issues. The second most frequently used source of information was television among several mass media sources. It is hoped that this study contributes to understanding the elementary school students' perceptions toward the selected Earth systems and environmental issues.

구연산을 이용한 스테인레스 스틸의 미세 전해가공 (Micro Electrochemical Machining of Stainless Steel Using Citric Acid)

  • 류시형
    • 한국정밀공학회지
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    • 제25권3호
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    • pp.134-140
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    • 2008
  • Micro electrochemical machining (ECM) is conducted on stainless steel 304 using non-toxic electrolyte of citric acid. Electrochemical dissolution region is minimized by applying a few hundred second duration pulses between the tungsten SPM tip and the work material. ECM characteristics according to citric acid concentration, feeding velocity and electric conditions such as pulse amplitude, pulse frequency, and offset voltage are investigated through a series of experiments. Micro holes of $60{\mu}m$ in diameter with the depth of $50{\mu}m$ and $90{\mu}m$ in diameter with the depth of $100{\mu}m$ are perforated. Square and circular micro cavities are also manufactured by electrochemical milling. This research can contribute to the development of safe and environmentally friendly micro ECM process.

ULTRAFAST INTERFACIAL ELECTRON TRAPPING AND RECOMBINATION IN PHOTOEXCITED COLLOIDAL CADMIUM SULFIDE

  • Kim, Seong-Kyu
    • Journal of Photoscience
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    • 제4권1호
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    • pp.11-16
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    • 1997
  • We measured, using femtosecond pump-probe experiment, the time evolution of transient absorption in aqueous CdS colloids. The signal rises within the time resolution (= 0.5 ps) of the experiment and decays with two exponential time constants, 4.8 ps and 132 ps. The ultrafast rise of the transient absorption is considered to be for shallowly trapped conduction band electrons after photoexcitation. The amplitude ratio of the two decaying components varies with the pump intensity and the decay times increase in the presence of hole scavengers. Even though a biexponential function fits the decay well, we object hat two independent first order processes (geminate and nongeminate recombinations) are responsible for the decay. A function with an integrated rate equation for second order nongeminate recombination plus a long background fits the decay well. The long background is considered to be for deeply trapped charges at the CdS particle.

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