• 제목/요약/키워드: $SrRuO_3$

검색결과 92건 처리시간 0.06초

Magnetic Properties of SrRuO3 Thin Films Having Different Crystal Symmetries

  • Kim, Jin-I;Jung, C.U.
    • Journal of Magnetics
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    • 제13권2호
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    • pp.57-60
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    • 2008
  • This study examined the effect of various types of epitaxial strain on the magnetic properties of $SrRuO_3$ thin films. Epitaxial $SrTiO_3$ (001), $SrTiO_3$ (110), and $SrTiO_3$ (111) substrates were used to apply different crystal symmetries to the grown films. The films were grown using pulsed laser deposition. The X-ray diffraction patterns of the films grown under optimum conditions showed very clear peaks for the $SrRuO_3$ film and $SrTiO_3$ substrates. The saturated magnetic moment at 5 K after 7 Tesla field cooling was $1.2-1.4\;{\mu}_B$/Ru. The magnetic easy axis for all three types of films was along the surface normal. The magnetic transition temperature for the $SrRuO_3$ film with lower symmetry was slightly larger than the $SrRuO_3$ film with higher symmetry.

Sr2Ru1-xCuxO4-y(0.0≤x≤0.5) 화합물의 구조 및 전달 특성에 대한 연구 (Study on the Structural and Transporting Property of Sr2Ru1-xCuxO4-y(0.0≤x≤0.5))

  • 박중철
    • 대한화학회지
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    • 제47권6호
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    • pp.614-618
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    • 2003
  • 고상반응으로 $Sr_2Ru_{1-x}Cu_xO_{4-y}(0.0{\le}x{\le}0.5)$ 화합물을 합성하였다. X-선 회절 분석 결과에 대한 Rietveld 정밀화로부터 합성된 $Sr_2Ru_{1-x}Cu_xO_{4-y}$ 화합물은 $0{\le}x{\le}0.30$의 Cu 치환 범위에서는 모두 단일상의 정방정계 구조를 갖는 $K_2NiF_4$ 형태의 구조를 취하지만, $0.4{\le}x{\le}0.5$의 범위에서는 미량의 $Sr_2CuO_3$ 화합물의 회절 피이크가 관찰되는 이중상을 갖는 화합물로 존재한다는 사실을 알 수 있었다. $Sr_2RuO_4$ 화합물의 Ru자리에 Cu 이온을 부분적으로 치환할 때의 전이금속 이온인, Ru와 Cu이온의 원자가 상태는 X-선 전자 분광법으로 확인하였다. $Ru\; 3p_{3/2}$ 전자와 $Cu\; 2p_{3/2}$ 전자의 결합에너지 측정으로부터 $Ru^{4+},\;Cu^{2+}$를 갖는 것으로 확인되었다. $Sr_2RuO_4$ 화합물의 Ru 자리에 치환하는 Cu 이온의 농도를 증가할수록 $Ru-O1({\times}4)$$Ru-O_2({\times}2$)의 결합길이 차이가 ${\Delta}=0.1329 {\AA}Sr_2RuO_4$ 경우)에서 ${\Delta}=0.0383 {\AA}(Sr_Ru_{0.7}Cu_{0.3}O_{4-y}$ 경우)으로 변하며, c/a 역시 감소하는 경향을 나타내고 있다. 따라서, $Sr_2RuO_4$ 화합물의 Ru 자리에 Cu 이온을 치환함에 따라 $RuO_6$ 팔면체의 국부 대칭성의 변화에 의해 결정구조가 정방정계로의 변화를 수반하면서, 이에 따른 $Sr_2Ru_{1-x}Cu_xO_{4-y}$의 전달특성이 금속에서 반도체로 변화한다.

Structural and Electrical Properties of SrRuO3 thin Film Grown on SrTiO3 (110) Substrate

  • Kwon, O-Ung;Kwon, Namic;Lee, B.W.;Jung, C.U.
    • Journal of Magnetics
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    • 제18권1호
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    • pp.39-42
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    • 2013
  • We studied the structural and electrical properties of $SrRuO_3$ thin films grown on $SrTiO_3$ (110) substrate. High resolution X-ray diffraction measurement of the grown film showed 1) very sharp peaks for $SrRuO_3$ film with a very narrow rocking curve with FWHM = $0.045^{\circ}$ and 2) coherent growth behavior having the same in-plane lattice constants of the film as those of the substrate. The resisitivity data showed good metallic behavior; ${\rho}$ = 63(205) ${\mu}{\Omega}{\cdot}cm$ at 5 (300) K with a residual resistivity ratio of ~3. The observed kink at ${\rho}(T)$ showed that the ferromagnetic transition temperature was ~10 K higher than that of $SrRuO_3$ thin film grown on $SrTiO_3$ (001) substrate. The observed rather lower RRR value could be partially due to a very small amount of Ru vacancy generally observed in $SrRuO_3$ thin films grown by PLD method and is evident in the larger unit-cell volume compared to that of stoichiometric thin film.

펄스 레이저 증착법으로 $SrRuO_3$/Si 구조위에서 증착된 강유전체 $Pb(Zr_{0.2}Ti_{0.8})O_3$ 박막 (The ferroelectric $Pb(Zr_{0.2}Ti_{0.8})O_3$ thin film growth on $SrRuO_3$/Si structure by pulsed laser deposition)

  • 함성길;윤순길
    • 한국전기전자재료학회:학술대회논문집
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    • 한국전기전자재료학회 2007년도 하계학술대회 논문집 Vol.8
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    • pp.302-302
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    • 2007
  • The $SrRuO_3$/Si thin film electrodes are grown with (00l) preferred orientations on SrO buffered-Si (001) substrates by pulsed laser deposition. The optimum conditions of SrO buffer layers for $SrRuO_3$ preferred orientations are the deposition temperature of $700^{\circ}C$, deposition pressure of $1\;{\times}\;10^{-6}\;Torr$, and the thickness of 6 nm. The 100nm thick-$SrRuO_3$ bottom electrodes deposited above $650^{\circ}C$ on SrO buffered-Si (001) substrates have a rms roughness of approximately $5.0\;{\AA}$ and a resistivity of 1700 -cm, exhibiting a (00l) relationship. The 100nm thick-$Pb(Zr_{0.2}Ti_{0.8})O_3$ thin films deposited at $575^{\circ}C$ have a (00l) preferred orientation and exhibit $2P_r$ of $40\;C/cm^2$, $E_c$ of 100 kV/cm, and leakage current of about $1\;{\times}\;10^{-7}\;A/cm^2$ at 1V.

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