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Thickness Dependence of the Crystallization of FePt/MgO(001) Magnetic Thin Films

FePt/MgO(001) 자성박막 결정화의 두께의존성

  • 정지욱 (경북대학교 나노소재공학부) ;
  • 이민수 (경북대학교 나노소재공학부) ;
  • 조태식 (경북대학교 나노소재공학부)
  • Published : 2010.02.01

Abstract

The crystallization of FePt/MgO(001) magnetic thin films of various thicknesses has been studied using synchrotron x-ray scattering, atomic force microscope, and vibrating sample magnetometer. In film with a 499-$\AA$-thick, face-centered tetragonal, ordered FePt phase was dominantly crystallized into perpendicular (001) grains keeping the magnetically easy c-axis normal to the film plane during annealing. In film with a 816-$\AA$-thick, however, longitudinal (110) grains keeping the c-axis parallel to the film plane were grown on top of the perpendicular (001) grains. The behavior of the magnetic properties was consistent with the thickness dependence of the crystallization. We attribute the thickness dependence of the crystallization to the substrate effect, which prefers the growth of the c-axis oriented perpendicular grains near the film/substrate interfacial area.

Keywords

References

  1. M. F. Toney, W.-Y. Lee, J. A. Hedstrom, and A. Kellock, “Thickness and growth temperature dependence of structure and magnetism in FePt thin films”, J. Appl. Phys., Vol. 93, No. 12, p. 9902, 2003. https://doi.org/10.1063/1.1577226
  2. Y. K. Takahashi, M. Ohnuma, and K. Hono, “Ordering process of sputtered FePt films”, J. Appl. Phys., Vol. 93, No. 10, p. 7580, 2003. https://doi.org/10.1063/1.1538174
  3. M. R. Visokay and R. Sinclair, “Direct formation of ordered CoPt and FePt compound thin films by sputtering”, Appl. Phys. Lett., Vol. 66, No. 13, p. 1692, 1995. https://doi.org/10.1063/1.113895
  4. R. F. C. Farrow, D. Weller, R. F. Marks, and M. F. Toney, “Growth temperature dependence of long-range alloy order and magnetic properties of epitaxial $Fe_xPt_{1-х}$(x =0.5) films”, Appl. Phys. Lett., Vol. 69, No. 8, p. 1166, 1996. https://doi.org/10.1063/1.117383
  5. T. S. Cho, J. H. Je, and D. Y. Noh, “Formation of crystalline Ba-ferrite phase from ${\alpha}-Fe_2O_3$ phase in amorphous precursor”, Appl. Phys. Lett., Vol. 76, No. 3, p. 303, 2000. https://doi.org/10.1063/1.125727
  6. T. S. Cho, S. J. Doh, J. H. Je, and D. Y. Noh, “Microstructure of epitaxial ${\alpha}-Fe_2O_3$ grains in Ba-ferrite thin films grown on sapphire(001)”, Appl. Phys. Lett., Vol. 74, No. 14, p. 2050, 1999. https://doi.org/10.1063/1.123753
  7. T.-S. Cho, S. J. Doh, J. H. Je, and D. Y. Noh, “Thickness dependence of the crystallization of Ba-ferrite films”, J. Appl. Phys., Vol. 86, No. 4, p. 1958, 1999. https://doi.org/10.1063/1.370993
  8. 조태식, “a-$Fe_2O_3/a-Al_2O_3$(0001) 박막 결정화의 방사광 x-선 산란 연구”, 전기전자재료학회논문지, 15권 8호, p. 708, 2002. https://doi.org/10.4313/JKEM.2002.15.8.708
  9. 조태식, “방사광 x-선 기법에 의한 다층형 Fe/Cr 자성박막의 계면확산 연구”, 전기전자재료학회논문지, 17권 2호, p. 223, 2004. https://doi.org/10.4313/JKEM.2004.17.2.223
  10. B. D. Cullity, "자성재료학", (주) 피어슨 에듀케이션 코리아, p. 91, 2001.
  11. B. D. Cullity, S. R. Stock, "X선 회절", 진샘 미디어 p. 175, 608, 2006.