Hostname: page-component-8448b6f56d-qsmjn Total loading time: 0 Render date: 2024-04-23T15:53:08.767Z Has data issue: false hasContentIssue false
  • English
  • Français

Large Anisotropy Via Oblique Sputtering of Ta Underlayers

Published online by Cambridge University Press:  14 March 2011

J.E. Bonevich ,
R.D. McMichael ,
C.G. Lee ,
P.J. Chen ,
W. Miller  and
W.F. Egelhoff
J.E. Bonevich
Affiliation:
National Institute of Standards and Technology, Gaithersburg, MD 20899, USA
R.D. McMichael
Affiliation:
National Institute of Standards and Technology, Gaithersburg, MD 20899, USA
C.G. Lee
Affiliation:
Changwon National University, Changwon, Kyungnam 641-773, KOREA
P.J. Chen
Affiliation:
National Institute of Standards and Technology, Gaithersburg, MD 20899, USA
W. Miller
Affiliation:
National Institute of Standards and Technology, Gaithersburg, MD 20899, USA
W.F. Egelhoff
Affiliation:
National Institute of Standards and Technology, Gaithersburg, MD 20899, USA
Get access

Abstract

Anisotropy fields in excesss of 120kA/m(1500Oe)have been produced in 3 nm to 5 nm thick polycrystalline films of Co with Ta underlayers. The unusualy high anisotropy is magnetostatic in origin, and is induced by corrugations on the surface of an obliquely sputtered Ta underlayer. Cross-sectional TEM reveas 8 nm columnar grains of Ta tilted toward the Ta source and elongated perpendicuar to the Ta flux in the film plane. The anisotropy field of the Co film increases with both the underlayer thickness and the angle between theTa source and the film normal. In spin valve samples, the anisotropy is attenuated by more than an order of magnitude across a 4nm thick Cu spacer. Magnetoresistance measurements on a spin valve indicate less than 2° dispersion in hard axis directions, and despite the nanometer-scale roughness of the underlayer, there is weak broadening of the ferromagnetic resonance line.

Type
Research Article
Information
MRS Online Proceedings Library (OPL) , Volume 614: Symposium F – Magnetic Materials, Structures & Processing for Information… , 2000 , F7.7.1
Copyright
Copyright © Materials Research Society 2000

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

REFERENCES

1. Smith, D.O., Appl. Phys. Suppl., 30, 264S (1959).10.1063/1.2185921Google Scholar
2. Knorr, T.G., and Hoffman, R.W., Phys.Rev., 113, 1039 (1959).10.1103/PhysRev.113.1039Google Scholar
3. Hoshi, Y., Suzuki, E., and Naoe, M., J. Appl. Phys., 79, 4945 (1996).10.1063/1.361597Google Scholar
4. Itoh, K., Hara, K., Kamiya, M., Okamoto, K., Hashimoto, T., and Fujiwara, H., J. Magn. Magn. Mater., 148, 132 (1995)10.1016/0304-8853(95)00178-6Google Scholar
5. Alameda, J.M., Carmona, F., Salas, F.H., Alvarez-Prado, L.M., Morales, R., and Perez, G.T., J. Magn.Magn.Mater., 154, 249 (1996)10.1016/0304-8853(95)00577-3Google Scholar
6. Tanaka, K., Yamauchi, S., E, Makino, Fuji, T., Inoue, M., and Izaki, M., IEEE Trans. Mag., 35, 2916 (1999).10.1109/20.801024Google Scholar
7. Otiti, T., Niklasson, G.A., Svedlindh, P., and Granqvist, C.G., Thin Solid Films, 307, 245 (1997).10.1016/S0040-6090(97)00257-5Google Scholar
8. Tait, R.N., Smy, T., and Brett, M.J., J. Vac.Sci.Technol.A, 10, 1518 (1992).10.1116/1.578037Google Scholar
9. Zhao, Y.P., Palasantzas, G., Wang, G.C., and Howwon, J. Th.M.De, Phys. Rev. B, 60, 1216 (1999).10.1103/PhysRevB.60.1216Google Scholar
10. Palasantzas, G.,J. Appl.Phys., 86, 2196(1999).10.1063/1.371030Google Scholar
11. Teng, E. and Ballard, N., IEEE Trans. MAG, 22, 579 (1986)10.1109/TMAG.1986.1064570Google Scholar
12. Twisselmann, D.J., Farhoud, M., Smith, H.I., and Ross, C.A., J.Appl. Phys., 85, 4292 (1999)10.1063/1.370346Google Scholar
13. Kim, J.-H. and Shin, S.-C., Jpn.J.Appl.Phys., 35, 342 (1996).10.1143/JJAP.35.342Google Scholar
14. http://math.nist.gov/oommf/Google Scholar
15. McMichael, R.D., Lee, C.G., Bonevich, J.E., Chen, P.J., Miller, W., and Egelhoff, W.F., J. Appl.Phys., 88, (2000), in press.Google Scholar
16. Lee, C.G. gratefully acknowledges a 2000 international cooperative research grant from the Korea Science and Engineering Foundation.Google Scholar