• 제목/요약/키워드: KWON-GA

검색결과 488건 처리시간 0.031초

Design and Fabrication of AlGaAs/GaAs MESFET for Minimizing Leakage Current

  • Hak, Lee-Byung;Rak, Yoon-Jung;Yul, Kwon-Jung;Yong, Lee-Heon;Rea, Jeong-Young;Hyun, Kwak-Myung;Sung, Ma-Dong
    • 한국전기전자재료학회:학술대회논문집
    • /
    • 한국전기전자재료학회 1996년도 추계학술대회 논문집
    • /
    • pp.160-163
    • /
    • 1996
  • To develope output characteristics of GaAs MESFET, which utilized in high frequency ranges, $Al_{0.2}$Ga$_{0.8}$As/GaAs layer was used. In this case, to minimize effects of deep-level in $Al_{0.2}$Ga$_{0.8}$As/GaAs layer, aluminium mole fraction was design to 0.2. HP 4145B was used in measurement, I$_{dss}$ was 25mA when V$_{G}$=0. Maximum transconductance was 168.75mS/mm, electron mobility was 3750 $\textrm{cm}^2$/V-s, therefore, it must be suitable for active device in MMIC. Also, Ideality factor was 1.26, which was similar to that of ideal schottky diode.

  • PDF

(F, Ga) 코도핑된 ZnO 투명 전도 박막의 솔-젤 제조와 특성 (Sol-gel Spin-coating of ZnO Co-doped with (F, Ga) as A Transparent Conducting Thin Film)

  • 남길모;권명석
    • 반도체디스플레이기술학회지
    • /
    • 제13권1호
    • /
    • pp.91-95
    • /
    • 2014
  • (F,Ga) co-doped ZnO thin film on glass substrate was fabricated via a simple non-alkoxide sol-gel spin-coating. Contrary to the F single doped ZnO thin film, the (F,Ga) co-doped thin film showed a significant reduce in electrical resistivity after a second post-heat-treatment in reducing environment. The resulting decrease in electrical resistivity with Ga co-doping is considered to be resulted from the increases both carrier density and mobility. The optical transmittance of the (F,Ga) co-doped thin film in the visible range showed higher transmittance with Ga co-doping compared with F single doped ZnO thin film.

Reactioin Characteristics of the Sm2Fe17-xGax(x0, 2) Alloy with Hydrogen and Methane Gas

  • Shon, S.W;Kwon, H.W
    • Journal of Magnetics
    • /
    • 제4권4호
    • /
    • pp.123-127
    • /
    • 1999
  • The Ga-stabilised $Sm_2Fe_{17-}$type alloy can hardly be disproportionated under ordinary HDDR condition. The HDDR characteristics of Ga-substituted $Sm_2Fe_{17-}$type alloy were examined, and, in particular, the effect of particle size on the disproportionation of the Ga-substituted alloy was investigated in detail. The reaction characteristics of the $Sm_2Fe_{17-}$type alloys with or without Ga-substitution with methane (CH4) gas are also examined. The Ga-stabilised $Sm_2Fe_{17-}$type alloy was able to be disproportionated significantly on heating up to 80$0^{\circ}C$ under hydrogen with normal pressure. The particle size influenced significantly on the disproportion-ation of the Ga-substitute alloy, and the materials with finer particle size (<40 ${\mu}{\textrm}{m}$) was fully disproportionated on heating up to around 80$0^{\circ}C$ under hydrogen gas with normal pressure. The Ga-substituted alloy has a very sluggish recombination kinetics with respect to the alloy without Ga-substitution. The $Sm_2Fe_{17}C_{x-}$type carbide was stabilised significantly by the Ga-substitution for Fe in the parent alloy. While the $Sm_2Fe_{17}C_x$ was disproportionated below 80$0^{\circ}C$ the Ga-stabilised $Sm_2Fe_{14}Ga_2C_x$ carbide remained intact even on heating up to 80$0^{\circ}C$.

  • PDF

ZnGa2O4 형광체 타겟의 제작 및 특성분석 (Fabrication and Characterization of ZnGa2O4 Phosphor Target)

  • 김용천;홍범주;권상직;김경환;박용서;최형욱
    • 한국전기전자재료학회논문지
    • /
    • 제17권12호
    • /
    • pp.1347-1351
    • /
    • 2004
  • The ZnGa$_2$O$_4$ phosphor target was synthesized through solid-state reactions as calcine and sintering temperature in order to deposit ZnGa$_2$O$_4$ Phosphor thin film by rf magnetron sputtering system. The x-ray diffraction patterns of ZnGa$_2$O$_4$ phosphor target showed the position of (311) main peak. The cathodoluminescence(CL) spectrums of ZnGa$_2$O$_4$ phosphor target showed main peak of 370 nm to 400 nm, and maximum intensity at the calcine temperature of $700^{\circ}C$ and sintering temperature of 130$0^{\circ}C$. It was possible to prepare The ZnGa$_2$O$_4$ phosphor thin film with synthesized ZnGa$_2$O$_4$ phosphor target and The prepared ZnGa$_2$O$_4$ phosphor thin film showed the position of (311) main peak.

Effect of Ga, Nb Addition on Disproportionation Kinetics of Nd-Fe-B Alloy

  • Kwon, H.W.;Yu, J.H.
    • Journal of Magnetics
    • /
    • 제14권4호
    • /
    • pp.150-154
    • /
    • 2009
  • The effect of Ga and, Nb addition on the kinetics and mechanism of the disproportionation of a Nd-Fe-B alloy were investigated by isothermal thermopiezic analysis (TPA) using $Nd_{12.5}Fe_{(81.1-(x+y))}B_{6.4}Ga_xNb_y$ (x=0 and 0.3, y= 0 and 0.2) alloys. The addition of Ga and Nb retarded the disproportionation kinetics of the Nd-Fe-B alloy significantly, and increased the activation energy of the disproportionation reaction. The disproportionation kinetics of the $Nd_{12.5}Fe_{(81.1-(x+y))}B_{6.4}Ga_xNb_y$ alloys measured under an initial hydrogen pressure of 0.02 MPa were fitted to a parabolic rate law. This suggested that during the disproportionation of $Nd_{12.5}Fe_{(81.1-(x+y))}B_{6.4}Ga_xNb_y$ alloys with an initial hydrogen pressure of 0.02 MPa, a continuous disproportionation product is formed and the overall reaction rate is limited by the diffusion of hydrogen atoms (or ions).

GA-SVM을 이용한 결함 경향이 있는 소프트웨어 모듈 예측 (Predicting Defect-Prone Software Module Using GA-SVM)

  • 김영옥;권기태
    • 정보처리학회논문지:소프트웨어 및 데이터공학
    • /
    • 제2권1호
    • /
    • pp.1-6
    • /
    • 2013
  • 소프트웨어의 결함 경향 모듈 예측을 위해 SVM 분류기가 우수한 성능을 보인다는 연구들이 많지만, SVM에서 필요한 파라미터 선정 시 매 커널마다 다르게 선정해야 하고, 파라미터의 변경에 따른 결과예측을 위해 알고리즘을 반복적으로 수행해야 하는 불편함이 있다. 따라서 본 논문에서는 SVM의 파라미터 선정 시 유전알고리즘을 이용하여 스스로 찾게 하는 GA-SVM 모델을 구현하였다. 그리고 분류 성능 비교를 위해 신경망의 역전파알고리즘을 이용하여 분류했던 기존 논문과 비교 분석한 결과, GA-SVM 모델의 성능이 더 우수함을 확인하였다.