• 제목/요약/키워드: molecular beam epitaxy

검색결과 352건 처리시간 0.032초

Li-doped p-type ZnS Grown by Molecular Beam Epitaxy

  • Lee Sang-Tae
    • Journal of Advanced Marine Engineering and Technology
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    • 제29권3호
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    • pp.313-318
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    • 2005
  • Li-doped ZnS layers were grown by molecular beam epitaxy. It was found that relatively low growth temperature is suitable for effective incorporation of Li acceptors. The layers grown under optimized conditions exhibited photoluminescence spectra dominated by neutral-acceptor-bound excitons. Such layers also showed electrically p-type behavior in capacitance-voltage characteristics. The net acceptor concentration is estimated to be approximately $3{\times}10^{15}\;cm^{-3}$.

펄스레이저증착법을 이용한 $\textrm{LaAlO}_3$ 박막의 Molecular Beam Epitaxy 성장 (Molecular Beam Epitaxy Grouth of $\textrm{LaAlO}_3$ Thin Film by a Pulsed laser Deposition Technique)

  • 김인선;허남회;박용기
    • 한국재료학회지
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    • 제9권1호
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    • pp.25-29
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    • 1999
  • We have developed a laser molecular beam epitaxy system for the layer-by-layer growth of oxide thin films. Using this system, we could grow and control oxide thin films of LaAlO$_3$in a molecular layer epitaxy mode on the atomically flat SrTiO$_3$ substrate with a LaAlO$_3$single crystal target. Very clear RHEED oscillations were observed during to growth of a LaAlO$_3$ film for a long period under the optimized conditions of substrate temperature at $650^{\circ}C$, oxygen pressure at 1$\times$10\ulcorner torr, and an incident laser fluence of 4.6J/$\textrm{cm}^2$. The height of mono-layer-LaAlO$_3$ film grown during one period of RHEED intensity oscillation was 3.8$\AA$.

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분자선 에피성장법으로 성장된 ZnSe/GaAs의 특성 (Property of molecular beam epitaxy-grown ZnSe/GaAs)

  • 김은도;손영호;조성진;황도원
    • 한국결정성장학회지
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    • 제17권2호
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    • pp.52-56
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    • 2007
  • 본 연구에서는 초고진공(UHV, ultra high vacuum) 분자선 에피성장(MBE, molecular beam epitaxy) 시스템을 제작하여, ZnSe/GaAs[001]을 증착하였고, 증착된 박막의 특성을 SEM(scanning electron microscopy), AFM(atomic force microscopy)으로 조사하여, 분자층 단위의 조밀하고 균일한 표면특성을 보이고 있음을 확인할 수 있었다 XRD(x-ray diffractometer)를 이용하여, GaAs[001]기판의 XRD peak 위치와 ZnSe 박막의 XRD peak 위치가 각자 일치함을 확인할 수 있었다. PL(photoluminescence)로는 대략 437nm에서 발광하는 것이 관측되었으며, 2인치 ZnSe 박막의 PL mapping을 측정하였다.

Molecular beam epitaxy법에 의한 희토류 이온$(Nd^{3+},\;Er^{3+})$ 첨가 $CaF_{2}$ 박막의 성장 (Growth of $CaF_{2}:R^{+3}$ (R=Nd, Er) layers by molecular beam epitaxy)

  • 고정민
    • 한국결정성장학회지
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    • 제9권1호
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    • pp.1-5
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    • 1999
  • Molecular beam epitaxy법으로 $CaF_{2}$ (111) 기판위에 희토류 이온 ($(Nd^{3+},\;Er^{3+})$) 첨가 $CaF_{2}$ 박막을 성장하였다. 첨가농도와 박막두께에 따른 희토류 첨가 $CaF_{2}$ 박막의 표면구조와 결정성을 RHEED로 검토하였다. 반도체 관련 고집적회로구조에 있어서의 완층막으로서의 응용을 고려하여, 희토류첨가 $CaF_{2}$ 박막과 $CaF_{2}$ (111) 기판과의 격자부정합의 변이를 X-ray rocking Curve 분석에 의해 검토하였다.

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초고진공 분자선 에피성장 시스템의 제작과 에피성장된 ZnSe/GaAs(001)의 광학특성 (Construction of an Ultra High Vacuum Molecular Beam Epitaxy System and Optical Property of ZnSe/GaAs(001) Epitaxial films)

  • 김은도;손영호;엄기석;조성진;황도원
    • 한국진공학회지
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    • 제15권5호
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    • pp.458-464
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    • 2006
  • 본 연구에서는 초고진공 (UHV; ultra high vacuum) 분자선 에피성장 (MBE; molecular beam epitaxy) 시스템의 제작과 성능연구가 성공적으로 이루어졌다. 초고진공 용 분자선 에피성장 시스템을 국산화개발 및 제작하여, 장비에 관한 성능 테스트를 하게 되었다. 본 장비의 진공도가 $2X10^{10}$ Torr에 도달함을 확인하였고, 시편 가열모듈(substrate heating module)이 $1,100^{\circ}C$까지 가열됨을 확인할 수 있었으며, ZnSe/GaAs(001)의 증착특성을 SEM (scanning electron microscope), AFM (atomic force microscope), XRD (x-ray diffraction), PL (photoluminescence) 등으로 조사하였다.

p-Type Doping of GaSb by Beryllium Grown on GaAs (001) Substrate by Molecular Beam Epitaxy

  • Benyahia, Djalal;Kubiszyn, Lkasz;Michalczewski, Krystian;Keblwski, Artur;Martyniuk, Piotr;Piotrowski, Jozef;Rogalski, Antoni
    • JSTS:Journal of Semiconductor Technology and Science
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    • 제16권5호
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    • pp.695-701
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    • 2016
  • Be-doped GaSb layers were grown on highly mismatched semi-insulating GaAs substrate (001) with $2^{\circ}$ offcut towards <110> at low growth temperature, by molecular beam epitaxy (MBE). The influence of Be doping on the crystallographic quality, surface morphology, and electrical properties, was assessed by X-ray diffraction, Nomarski microscopy, and Hall effect measurements, respectively. Be impurities are well behaved acceptors with hole concentrations as high as $9{\times}10^{17}cm^{-3}$. In addition, the reduction of GaSb lattice parameter with Be doping was studied.

Molecular Beam Epitaxy of InAs/AlSb HFET's on Si and GaAs Substrates

  • Oh, Jae-Eung;Kim, Mun-Deok
    • JSTS:Journal of Semiconductor Technology and Science
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    • 제6권3호
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    • pp.131-135
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    • 2006
  • High electron mobility transistors with InAs channels and antimonide barriers were grown on Si and GaAs substrates by means of molecular beam epitaxy. While direct growth of Sb materials on Si substrate generates disordered and coalescences 3-D growth, smooth and mirror-like 2D growth can be repeatedly obtained by inserting AlSb QD layers between them. Room-temperature electron mobilities of over 10,000 $cm^2/V-s$ and 20,000 $cm^2/v-s$ can be routinely obtained on Si and GaAs substrates, respectively, after optimizing the buffer structure as well as maintaining InSb-like interface.

Epitaxial Growth of MgO and CoFe/MgO on Ge(001) Substrates by Molecular Beam Epitaxy

  • Jeon, Kun-Rok;Park, Chang-Yup;Shin, Sung-Chul
    • 한국자기학회:학술대회 개요집
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    • 한국자기학회 2009년도 정기총회 및 동계학술연구발표회
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    • pp.190-190
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    • 2009
  • We report the epitaxial growth of MgO and CoFe/MgO on Ge (001) substrates using molecular beam epitaxy. It was found that the epitaxial growth of a MgO film on Ge could be realized at a low growth temperature of $125{\pm}5^{\circ}C$ and the MgO matches the Ge with a cell ratio of $\sqrt{2}$:1 which renders MgO rotated by $45^{\circ}$ relative to Ge. In-situ and ex-situ structural characterizations reveal the epitaxial crystal growth of bcc CoFe/MgO on Ge with the in-plane crystallographic relationship of CoFe(001)[100] || MgO(001)[110] || Ge(001)[100], exhibiting sharp interfaces in the (001) matching planes. The saturation magnetization of the sample is $1430{\pm}20$ emu/cc, which is comparable to the value of bulk CoFe.

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Reflection High Energy Electron Diffraction이 결합된 Laser Molecular Beam Epitaxy System에서 $BaTiO_3/SrTiO_3$ 산화물 인공격자의 Layer-by-Layer 성장 (Atomic Layer-by-Layer Growth of $BaTiO_3/SrTiO_3$ Oxide Artificial Lattice in Laser Molecular Beam Epitaxy System Combined Reflection High Energy Electron Diffraction)

  • 이창훈;김이준;전성진;김주호;최택집;이재찬
    • 한국세라믹학회:학술대회논문집
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    • 한국세라믹학회 2003년도 추계총회 및 연구발표회 초록집
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    • pp.179.2-179
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    • 2003
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Potential for Novel Magnetic Structures by Nanowire Growth Mechanisms

  • Lapierre R.R.;Plante M.C.
    • Journal of Magnetics
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    • 제10권3호
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    • pp.108-112
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    • 2005
  • GaAs nanowires were grown on GaAs (111)B substrates in a gas source molecular beam epitaxy system, using self-assembled Au particles with diameters between 25 and 200 nm as the catalytic agents. The growth rate and structure of the nanowires were investigated for substrate temperatures between 500 and $600^{\circ}C$ to study the mass transport mechanisms that drive the growth of these crystals. The possibilities for fabrication of novel magnetic nanostructures by suitable choice of growth conditions are discussed.