한국초전도ㆍ저온공학회논문지 (Progress in Superconductivity and Cryogenics)

  • 제15권2호
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  • Pages.9-11
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  • 2013
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  • 1229-3008(pISSN)
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  • 2287-6251(eISSN)
한국초전도저온학회 (The Korean Society of Superconductivity and Cryogenics)
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Thickness dependence of grain growth orientation in MgB2 films fabricated by hybrid physical-chemical vapor deposition

  • Ranot, Mahipal (BK21 Physics Division and Department of Physics, Sungkyunkwan University) ;
  • Kang, W.N. (BK21 Physics Division and Department of Physics, Sungkyunkwan University)
  • 투고 : 2013.05.23
  • 심사 : 2013.06.27
  • 발행 : 2013.06.30
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초록

We have investigated the effect of thickness of the MgB2 film on the grain growth direction as well as on their superconducting properties. $MgB_2$ films of various thicknesses were fabricated on c-cut $Al_2O_3$ substrates at a temperature of $540^{\circ}C$ by using hybrid physical-chemical vapor deposition (HPCVD) technique. The superconducting transition temperature ($T_c$) was found to increase with increase in the thickness of the $MgB_2$ film. X-ray diffraction analysis revealed that the orientation of grains changed from c-axis to a-axis upon increasing the thickness of the $MgB_2$ film from 0.6 to 2.0 ${\mu}m$. $MgB_2$ grains of various orientations were observed in the microstructures of the films examined by scanning electron microscopy. It is observed that at high magnetic fields the 2.0-${\mu}m$-thick film exhibit considerably larger critical current density ($J_c$) as compared to 0.6-${\mu}m$-thick film. The results are discussed in terms of an intrinsic-pinning in $MgB_2$ similarly as intrinsic-pinning occurring in high-Tc cuprate superconductors with layered structure.

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참고문헌

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