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Analytical TEM Examinations of CoPt-TiO2 Perpendicular Magnetic Recording Media

Published online by Cambridge University Press:  19 March 2007

Juliet D. Risner
Affiliation:
Department of Materials Science and Engineering, Stanford University, Stanford, CA 94305-2205, USA
Thomas P. Nolan
Affiliation:
Seagate Media Research Center, Fremont, CA 94538, USA
James Bentley
Affiliation:
Materials Science and Technology Division, Oak Ridge National Laboratory, Oak Ridge, TN 37831-6064
Erol Girt
Affiliation:
Seagate Media Research Center, Fremont, CA 94538, USA
Samuel D. Harkness IV
Affiliation:
Seagate Media Research Center, Fremont, CA 94538, USA
Robert Sinclair
Affiliation:
Department of Materials Science and Engineering, Stanford University, Stanford, CA 94305-2205, USA
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Abstract

For this analytical TEM study, nonmagnetic oxygen-rich boundaries were introduced into Co-Pt-alloy perpendicular recording media by cosputtering Co and Pt with TiO2. Increasing the TiO2 content resulted in changes to the microstructure and elemental distribution within grains and boundaries in these films. EFTEM imaging was used to generate composition maps spanning many tens of grains, thereby giving an overall depiction of the changes in elemental distribution occurring with increasing TiO2 content. Comparing EFTEM with spectrum-imaging maps created by high-resolution STEM with EDXS and EELS enabled both corroboration of EFTEM results and quantification of the chemical composition within individual grain boundary areas. The difficulty of interpreting data from EDXS for these extremely thin films is discussed. Increasing the TiO2 content of the media was found to create more uniformly wide Ti- and O-rich grain boundaries as well as Ti- and O-rich regions within grains.

Type
MATERIALS APPLICATIONS
Copyright
© 2007 Microscopy Society of America

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References

REFERENCES

Bentley, J., Wittig, J.E. & Nolan, T.P. (1998). Quantitative measurements of segregation in Co-Cr-X magnetic recording media by energy-filtered transmission electron microscopy. Mat Res Soc Symp Proc 517, 205210.Google Scholar
Bertram, H.N. & Williams, M. (2000). SNR and density limit estimates: A comparison of longitudinal and perpendicular recording. IEEE Trans Magn 36, 49.Google Scholar
Egerton, R.F. (1996). Electron Energy-Loss Spectroscopy in the Electron Microscope, 2nd ed. New York: Plenum Press.
Futamoto, M., Inaba, N., Hirayama, Y., Ito, K. & Honda, Y. (1999). Microstructure and micromagnetics of future thin-film media. J Magn Magn Mater 193, 3643.Google Scholar
Girt, E., Wu, S., Lu, B., Ju, G., Nolan, T., Harkness, S., Valcu, B., Dobin, A., Risner, J.D., Munteanu, M., Thangaraj, R., Chang, C.-H., Tran, T., Wu, X., Mryasov, O., Weller, D. & Hwang, S. (2006). Influence of oxide on the structural and magnetic properties of CoPt alloy. J Appl Phys 99, 08E715.Google Scholar
Jeanguillaume, C. & Colliex, C. (1989). Spectrum-image: The next step in EELS digital acquisition and processing. Ultramicroscopy 38, 252257.Google Scholar
Kwon, U., Sinclair, R., Velu, E.M.T., Malhotra, S. & Bertero, G. (2005). Ru/Ru-oxide interlayer for CoCrPtO perpendicular recording media. In Magnetics Conference, 2005. INTERMAG Asia 2005. Digests of the IEEE International, pp. 15791580. Nagoya, Japan: IEEE. [please visit http://ieeexplore.ieee.org/Xplore/dynhome.jsp]
Lu, B., Weller, D., Ju, G., Sunder, A., Karns, D., Wu, M. & Wu, X. (2003). Development of Co-alloys for perpendicular magnetic recording media. IEEE Trans Magn 39, 19081913.Google Scholar
Mattox, D.M. (1998). Handbook of Physical Vapor Deposition (PVD) Processing: Film Formation, Adhesion, Surface Preparation and Contamination Control. Park Ridge, NJ: Noyes Publications.
Oikawa, S., Takeo, A., Hikosaka, T. & Tanaka, Y. (2000). High performance CoPtCrO single layered perpendicular media with no recording demagnetization. IEEE Trans Magn 36, 23932395.Google Scholar
Risner, J.D., Sinclair, R. & Bentley, J. (2006). Observation of the effect of grain orientation on chromium segregation in longitudinal magnetic media. J Appl Phys 99, 033905.Google Scholar
Thornton, J.A. (1977). High rate thick film growth. Ann Rev Mater Sci 7, 239260.Google Scholar
Williams, D.B. & Carter, C.B. (1996). Transmission Electron Microscopy: A Textbook for Materials Science. New York: Plenum Press.
Wittig, J.E., Al-Sharab, J.F., Doerner, M., Bian, X., Bentley, J. & Evans, N.D. (2003). Influence of microstructure on the chemical inhomogeneities in nanostructured longitudinal magnetic recording media. Scripta Materialia 48, 943948.Google Scholar
Wittig, J.E., Bentley, J. & Nolan, T.P. (1999). Microstructural characterization methods for magnetic thin films. Mat Res Soc Symp Proc 562, 314.Google Scholar
Wittig, J.E., Nolan, T.P., Sinclair, R. & Bentley, J. (1998). Chromium distribution in CoCrTa/Cr longitudinal recording media. Mat Res Soc Symp Proc 517, 211216.Google Scholar
Zaluzec, N.J. (1979). Quantitative X-ray microanalysis: Instrumental considerations and applications to materials science. In Introduction to Analytical Electron Microscopy, Hren, J.J., Goldstein, J., Joy, D.C., Electron Microscopy Society of America, Microbeam Analysis Society (Eds.), pp. 121167. New York: Plenum Press.
Zheng, M., Acharya, B.R., Choe, G., Zhou, J.N., Yang, Z.D., Abarra, E.N. & Johnson, K.E. (2004). Role of oxygen incorporation in Co-Cr-Pt-Si-O perpendicular magnetic recording media. IEEE Trans Magn 40, 24982500.Google Scholar