Structural study of epitaxial $\beta-FeSi_2$ on Si (001) substrate by using density functional theory (DFT)

DFT를 이용한 $\beta-FeSi_2$/Si (001) 에피택셜 계면 연구

  • Hwang, Kyu-Cheol (Department of Materials Engineering, Korea University of Technology and Education) ;
  • Kim, Dae-Hee (Department of Materials Engineering, Korea University of Technology and Education) ;
  • Oh, Hyun-Chul (Department of Materials Engineering, Korea University of Technology and Education) ;
  • Rim, Ji-Hye (Department of Materials Engineering, Korea University of Technology and Education) ;
  • Kim, Yeong-Cheol (Department of Materials Engineering, Korea University of Technology and Education)
  • 황규철 (한국기술교육대학교 신소재공학과) ;
  • 김대희 (한국기술교육대학교 신소재공학과) ;
  • 오현철 (한국기술교육대학교 신소재공학과) ;
  • 임지혜 (한국기술교육대학교 신소재공학과) ;
  • 김영철 (한국기술교육대학교 신소재공학과)
  • Published : 2008.06.30

Abstract

An epitaxial $\beta-FeSi_2$ structure on Si (001) substrate was calculated by using density functional theory (DFT). Unit cell of orthorhombic $\beta-FeSi_2$ and $\sqrt{2}\times\sqrt{2}\times2$ supercell were calculated to find the energetically favorable structures first. The $\chi$- and y-direction axes of $\beta-FeSi_2$ were changed into y- and z-direction axes to match its structure with that of Si, to minimize the lattice mismatch between $\beta-FeSi_2$ and Si. Distance between the Si (001) surface and the $\beta-FeSi_2$ surface was varied to find an optimum distance between them, resulting in 0.825 $\AA$.

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