• 제목/요약/키워드: Kink phenomenon

검색결과 6건 처리시간 0.022초

Multi-Finger MOSFET의 바이어스 종속 S11-파라미터 분석 (An Analysis of Bias-Dependent S11-Parameter in Multi-Finger MOSFETs)

  • 안자현;이성현
    • 전자공학회논문지
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    • 제53권12호
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    • pp.15-19
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    • 2016
  • 매우 큰 사이즈를 가진 multi-finger RF MOSFET의 $S_{11}$-parameter에서 스미스차트의 저항 circle 라인을 벗어나는 kink 현상의 게이트 바이어스 종속 특성이 관찰되었다. 이러한 바이어스 종속성은 $S_{11}$-parameter의 크기와 위상, 입력저항, 입력 커패시턴스의 주파수 응답곡선을 측정하여 최초로 분석되었다. 그 결과 입력 커패시턴스의 크기와 입력저항의 dominant pole과 zero 주파수에 의해 $V_{gs}$ 종속 kink 현상이 크게 변하는 것을 알 수 있다. $V_{gs}=0V$일 때 매우 적은 $S_{11}$-parameter 위상차와 입력저항의 높은 pole 주파수에 의해 고주파영역에서 kink 현상이 나타난다. 하지만 $V_{gs}$가 높아지면 $S_{11}$-parameter 위상차가 크게 증가하고 pole 주파수가 낮아져 저주파영역에서 kink 현상이 발생하게 된다.

Investigation on the phase transition of $Ni_2$MnGa alloy by using impedance spectroscopy

  • Park, S.Y.;Cho, K.H.;Lee, Y.P.
    • Journal of Korean Vacuum Science & Technology
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    • 제7권1호
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    • pp.13-17
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    • 2003
  • The influence of structural transition on the resistance and impedance behavior of Ni$_2$MnGa alloy was investigated. The temperature-dependent resistance and impedance were measured in a temperature range of 4 - 350 K and 185 - 300 K, respectively. The dependence of temperature coefficient of resistivity on temperature shows a kink at 220 K, which is related to the structural transition. The change in dominant scattering mechanism results in the observed kink. Significant increases were also observed around the transition temperature for both real and imaginary parts of impedance. It is thought that this phenomenon originates from disappearance of the martensite twin boundaries during the structural transformation.

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꺾임이 발생한 연직배수재의 내부 막힘현상 (Effect of the Internal Clogging on the Kink Zone of PBD)

  • 김래현;홍성진;김재정;최영민;이우진
    • 한국지반공학회:학술대회논문집
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    • 한국지반공학회 2009년도 춘계 학술발표회
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    • pp.729-736
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    • 2009
  • Several well resistance effects induced by bending, confining stress, temperature, bubbles, and apparent opening size have been considered and researched for the reasonable PBD design. The effect of apparent opening size(AOS), however, was not extensively studied and the clogging effect by AOS was not clearly researched. In this paper, the slurry consolidation test which 4 types of PBD are installed in large slurry consolidometer($H{\times}D$, $2.0m{\times}1.2m$) is performed to investigate the clogging effect by filter's AOS. The results show that the internal clogging is observed all types of PBD, and a quantity of inflowed soil particles are increased at the lower part of PBD and the kink zone. In addition, the internal clogging phenomenon does not relate with the shape and size of PBD. In filter's AOS test, it was easily observed that soil particles bigger than AOS of tested filter passed PBD filter by SEM. This paper demonstrates that the reduction of discharge capability may be accelerated by internal clogging at the kink zone.

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Ge 농도에 따른 SGOI (Silicon-Germanium-On-Insulator) 1T-DRAM의 메모리 특성 (Memory characteristics of SGOI (Silicon-Germanium-On-Insulator) 1T-DRAM with various Ge mole fractions)

  • 오준석;김민수;정종완;이영희;정홍배;조현주
    • 한국전기전자재료학회:학술대회논문집
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    • 한국전기전자재료학회 2009년도 하계학술대회 논문집
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    • pp.99-100
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    • 2009
  • SGOI 1T-DRAM cells with various Ge mole fractions were fabricated and compared to the SOI 1T-DRAM cell. SGOI 1T-DRAM cells have a higher leakage current than SOI 1T-DRAM cell at subthreshold region. The leakage current due to crystalline defects and interface states at Si/SiGe increased with Ge mole. This phenomenon causes sensing margin and the retention time of SGOI 1T-DRAMs decreased with increase of Ge mole fraction.

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Offset 구조를 갖는 n-채널 다결정 실리콘 박막 트랜지스터의 I-V 분석 (The Analysis of I-V characteristics on n-channel offset gated poly-Si TFT`s)

  • 변문기;이제혁;김동진;조동희;김영호
    • 한국전기전자재료학회:학술대회논문집
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    • 한국전기전자재료학회 1999년도 춘계학술대회 논문집
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    • pp.26-29
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    • 1999
  • The I-V characteristics of the n-channel offset gated poly-Si TETs have been systematically investigated in order to analyse the effects of offset region. The on currents are reduced due to the series resistance by the offset length and there is no kink phenomenon in offset devices. The off currents of the offset gated TFTs are remarkably reduced to 10$^{-12}$ A independent of gate and drain voltage because the electric field is weakened by the increase of the depletion region width near the drain region. It is shown that the offset regions behave as a series resistance and reduce lateral and vertical electric field.

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절연체위의 다결정실리콘 재결정화 공정최적화와 그 전기적 특성 연구 (Optical process of polysilicaon on insulator and its electrical characteristics)

  • 윤석범;오환술
    • E2M - 전기 전자와 첨단 소재
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    • 제7권4호
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    • pp.331-340
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    • 1994
  • Polysilicon on insulator has been recrystallized by zone melting recrystallization method with graphite strip heaters. Experiments are performed with non-seed SOI structures. When the capping layer thickness of Si$\_$3/N$\_$4//SiO$\_$2/ is 2.0.mu.m, grain boundaries are about 120.mu.m spacing and protrusions reduced. After the seed SOI films are annealed at 1100.deg. C in NH$\_$3/ ambient for 3 hours, the recrystallized silicon surface has convex shape. After ZMR process, the tensile stress is 2.49*10$\^$9/dyn/cm$\^$2/ and 3.74*10$\^$9/dyn/cm$\^$2/ in the seed edge and seed center regions. The phenomenon of convex shape and tensile stress difference are completely eliminated by using the PSG/SiO$\_$2/ capping layer. The characterization of SOI films are showed that the SOI films are improved in wetting properties. N channel SOI MOSFET has been fabricated to investigate the electrical characteristics of the recrystallized SOI films. In the 0.7.mu.m thickness SOI MOSFET, kink effects due to the floating substrate occur and the electron mobility was calculated from the measured g$\_$m/ characteristics, which is about 589cm$\^$2//V.s. The recrystallized SOI films are shown to be a good single crystal silicon.

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