• Title/Summary/Keyword: Al-doped

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Enhancement mechanisms of luminance efficiency in red organic light-emitting devices fabricated utilizing a double electron transport layer consisting of an Al-doped layer and an undoped layer

  • Choo, D.C.;Bang, H.S.;Ahn, S.D.;Lee, K.S.;Seo, S.Y.;Yang, J.S.;Kim, T.W.;Seo, J.H.;Kim, Y.K.
    • 한국정보디스플레이학회:학술대회논문집
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    • 한국정보디스플레이학회 2008년도 International Meeting on Information Display
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    • pp.513-516
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    • 2008
  • The luminance efficiency of the red organic light-emitting devices fabricated utilizing a double electron transport layer (ETL) consisting of an Al-doped and an undoped layer was investigated. The Al atoms existing in the ETL acted as hole blocking sites, resulting in an increase in the luminance efficiency.

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Al-doped ZnO via Sol-Gel Spin-coating as a Transparent Conducting Thin Film

  • Nam, Gil-Mo;Kwon, Myoung-Seok
    • Journal of Information Display
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    • 제10권1호
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    • pp.24-27
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    • 2009
  • A simple nonalkoxide sol-gel route for depositing an Al-doped ZnO thin film on a glass substrate was derived in this study. The initial Al dopant concentration in the sol-gel preparation varied and ranged from 0 to 5%. The sol-gel-derived thin films showed c-plane preferred crystallization of their hexagonal phase, with nanosized grain structures. First and second post-heat-treatments were carried out to improve the film’s electrical resistivity. The carrier density and the Hall mobility were measured and discussed to explain the electrical resistivity. The optical transmittance within the visible range showed compatible properties, which indicates the possible use of A1-doped ZnO as a transparent electrode in flat panel displays.

단채널 덱타도핑 HEMT의 전압-전류 특성에 대한 2차원적 해석 (A Study on the I-V characteristics of a delta doped short-channel HEMT)

  • 이정호;채규수;김민년
    • 한국산학기술학회논문지
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    • 제5권4호
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    • pp.354-358
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    • 2004
  • 본 논문은 HEMT소자의 전류-전압특성을 해석적으로 모델링한 것으로 n-AlGaAs층의 전자농도를 고려하여 Gauss법칙과 비선형 전하제어모델을 이용하여 2DEG의 전자농도를 구하였고, 채널을 부분적으로 2차원적으로 해석하여 포화전압을 도출하였고, 계산된 결과는 n-AlGaAs의 전자농도를 고려하지 않은 결과와 비교하였을 때 비교적 정확한 전류전압특성을 보이고 있다

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고분자 P123와 란탄이 도핑된 알루미나의 특성 연구 (Characterization of Alumina Doped with Lanthanum and Pluronic P123 via Sol-Gel Process)

  • 정미원;이미회
    • 한국세라믹학회지
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    • 제45권5호
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    • pp.297-302
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    • 2008
  • To direct the evolution of nanostructure and immobilize ${\gamma}-Al_2O_3$ catalyst, nanocrystalline La-doped-$Al_2O_3$ powder were prepared by the sol-gel process with addition of an amphiphilic block copolymer template (pluronic P123: $(poly(ethyleneoxide)_{20}-poly(propyleneoxide)_{70}-poly(ethyleneoxide)_{20})$. The dried gel is amorphous, whereas heating at temperature above $700^{\circ}C$ leads to the formation of nanocrystalline ${\gamma}$ and ${\delta}-Al_2O_3$ and these two phases is kept until $1100^{\circ}C$. ${\alpha}-A1_2O_3 $starts to form at $1200^{\circ}C$ with $LaAl_{11}O_{18}$. The surface morphology and crystal structure has been observed by field emission scanning electron microscope (FE-SEM) and X-ray diffraction (XRD). Solid state $^{27}Al$ MAS NMR indicates two types of local environment, i.e. octahedral and tetrahedral sites. The surface area and pore size was compared among these powders using the BET nitrogen adsorption measurements.

Be을 첨가한 $CuAlO_2$ 세라믹의 전기적 특성 (Electrical properties of $CuAlO_2$ ceramics doped with Be)

  • 유영배;박민석;문병기;손세모;정수태
    • 한국전기전자재료학회:학술대회논문집
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    • 한국전기전자재료학회 2004년도 하계학술대회 논문집 Vol.5 No.2
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    • pp.675-678
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    • 2004
  • [ $CuAlO_2$ ] was used as P-type transparent conducting oxide. $CuAlO_2$ ceramics was obtained from heating a stoichiometric mixture of $Cu_2O$ and $Al_2OH_3$ at $1200^{\circ}C$ for 6h. $CuAlO_2$ ceramics were doped by the rate of 0, 5, 7 and 10% of the $BeSO_4{\cdot}4H_2O$. Sintered ceramics were investigated by X-ray diffraction (XRD) and electrical measurements. The room temperature conductivity of the ceramics, which were doped with $BeSO_4{\cdot}4H_2O$ 5wt% was of the order of $3.19\times10^{-3}S\;cm^{-1}$, and the density was $4.98g/cm^3$. Therefor the conductivity and density in $BeSO+4{\cdot}4H_2O$ 5wt% were better than other cases. Additionally, Seebeck cofficient measurements revealed that these ceramics were p-type semiconductors and the ceramic conductivity increased with the growth temperature.

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$BaTiO_3$계 세라믹의 $Al_{2}O_{3}$ 첨가에 따른 유전 특성 (Dielectric properties of $BaTiO_3$ system Ceramics Doped with $Al_{2}O_{3}$)

  • 허영식;이원섭;이성갑
    • 한국전기전자재료학회:학술대회논문집
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    • 한국전기전자재료학회 2001년도 추계학술대회 논문집 Vol.14 No.1
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    • pp.402-405
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    • 2001
  • $(Ba_{0.6-x}Sr_{0.4}Ca_{x})TiO_{3}$ (x=0.10, 0.15, 0.20) ceramics were fabricated by the mixed-oxide method and their stuctural and dielectric properties were investigated with variation of composition ratio and an amount of $Al_{2}O_{3}$ (0.5, 1.0, 1.5. 2.0, 3.0 wt%) doping content. As a result of the X-ray diffraction BSCT specimens showed dense and homogeneous structure without presence of the second phase. The sintered density was decreased with increase an $Al_{2}O_{3}$ doping content. The Curie temperature and relative dielectric constant at room temperature were decreased with increasing an amount of $Al_{2}O_{3}$ doping content. The dielectric loss is minimum for BSCT doped with 1.5wt% $Al_{2}O_{3}$ content. The tunability was decreased with increasing an Ca content and is about 4.2% for BSCT(50/40/10) doped with 2.0wt% $Al_{2}O_{3}$ content.

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