Published Online: 29 June 2015
Accepted: June 2015
Journal of Applied Physics 117, 243908 (2015); https://doi.org/10.1063/1.4923185
more...View Affiliations
We have investigated electrically conductive indium-zinc-oxide (IZO) deposited by magnetron sputtering as spacer layer for current-perpendicular-to-the-plane giant magnetoresistance sensor devices. Spin-valves with a Co50Fe50/IZO/Co50Fe50 trilayer showed resistance-area product (RA) ranging from 110 to 250 mΩ μm2, significantly larger than all-metal structures with Ag or Cu spacers (∼40 mΩ μm2). Magnetoresistance ratios (ΔR/R) of 2.5% to 5.5% depending on the IZO spacer thickness (1.5–6.0 nm), corresponding to ΔRA values from 3 to 13 mΩ μm2, were obtained. The values of ΔRA with the IZO spacers and Co50Fe50 magnetic layers were significantly larger than those with conventional metal spacers and Co50Fe50 magnetic layers (∼1–2 mΩ μm2). The dependence of ΔRA on the magnetic layer thickness suggests that the larger ΔRA obtained with IZO spacer is due to a large interfacial spin-dependent scattering caused by the large specific resistance at the Co50Fe50/IZO interface. From structural characterization by TEM and the observed dependence of the RA dispersion on device size, the electric current flowing through the IZO spacer is thought to be laterally uniform, similar to normal metal spacers.
We thank Elizabeth Brinkman and Brian York at HGST Materials Laboratory for RBS analysis, and Stefan Maat at HGST Recording Head Development for discussions.
  1. 1. T. Valet and A. Fert, Phys. Rev. B 48, 7099 (1993). https://doi.org/10.1103/PhysRevB.48.7099, Google ScholarCrossref
  2. 2. M. Takagishi, K. Koi, M. Yoshikawa, T. Funayama, H. Iwasaki, and M. Sahashi, IEEE Trans. Magn. 38, 2277 (2002). https://doi.org/10.1109/TMAG.2002.802804, Google ScholarCrossref
  3. 3. H. Fukuzawa, H. Yuasa, S. Hashimoto, K. Koi, H. Iwasaki, M. Takagishi, Y. Tanaka, and M. Sahashi, IEEE Trans. Magn. 40, 2236 (2004). https://doi.org/10.1109/TMAG.2004.829185, Google ScholarCrossref
  4. 4. M. Saito, N. Hasegawa, Y. Ide, T. Yamashita, Y. Hayakawa, Y. Nishiyama, M. Ishizone, S. Yanagi, K. Honda, N. Ishibashi, D. Aoki, H. Kawanami, K. Nishimura, J. Takahashi, and A. Takahashi, Dig. Intermag Conf. Asia 2005, 1217. https://doi.org/10.1109/INTMAG.2005.1464038, Google ScholarCrossref
  5. 5. J. R. Childress, M. J. Carey, M.-C. Cyrille, K. Carey, N. Smith, J. A. Katine, T. D. Boone, A. A. G. Driskill-Smith, S. Maat, K. Mackay, and C. H. Tsang, IEEE Trans. Magn. 42, 2444 (2006). https://doi.org/10.1109/TMAG.2006.878815, Google ScholarCrossref
  6. 6. K. Yakushiji, K. Saito, S. Mitani, K. Takanashi, Y. K. Takahashi, and K. Hono, Appl. Phys. Lett. 88, 222504 (2006). https://doi.org/10.1063/1.2207987, Google ScholarScitation, ISI
  7. 7. K. Nikolaev, P. Anderson, P. Kolbo, D. Dimitrov, S. Xue, X. Peng, T. Pokhil, H. Cho, and Y. Chen, J. Appl. Phys. 103, 07F533 (2008). https://doi.org/10.1063/1.2839344, Google ScholarScitation
  8. 8. T. Furubayashi, K. Kodama, H. Sukegawa, Y. K. Takahashi, K. Inomata, and K. Hono, Appl. Phys. Lett. 93, 122507 (2008). https://doi.org/10.1063/1.2990647, Google ScholarScitation, ISI
  9. 9. S. Maat, M. J. Carey, and J. R. Childress, Appl. Phys. Lett. 93, 143505 (2008). https://doi.org/10.1063/1.2993213, Google ScholarScitation
  10. 10. T. Iwase, Y. Sakuraba, S. Bosu, K. Saito, S. Mitani, and K. Takanashi, Appl. Phys. Express 2, 063003 (2009). https://doi.org/10.1143/APEX.2.063003, Google ScholarCrossref
  11. 11. K. Shimazawa, Y. Tsuchiya, T. Mizuno, S. Hara, T. Chou, D. Miyauchi, T. Machita, T. Ayukawa, T. Ichiki, and K. Noguchi, IEEE Trans. Magn. 46, 1487 (2010). https://doi.org/10.1109/TMAG.2010.2042574, Google ScholarCrossref
  12. 12. T. M. Nakatani, T. Furubayashi, and K. Hono, J. Appl. Phys. 109, 07B724 (2011). https://doi.org/10.1063/1.3554206, Google ScholarScitation, ISI
  13. 13. Y. K. Takahashi, A. Srinivasan, B. Varaprasad, A. Rajanikanth, N. Hase, T. M. Nakatani, S. Kasai, T. Furubayashi, and K. Hono, Appl. Phys. Lett. 98, 152501 (2011). https://doi.org/10.1063/1.3576923, Google ScholarScitation, ISI
  14. 14. M. J. Carey, S. Maat, S. Chandrashekariaih, J. A. Katine, W. Chen, B. York, and J. R. Childress, J. Appl. Phys. 109, 093912 (2011). https://doi.org/10.1063/1.3563578, Google ScholarScitation, ISI
  15. 15. J. Sato, M. Oogane, H. Naganuma, and Y. Ando, Appl. Phys. Express 4, 113005 (2011). https://doi.org/10.1143/APEX.4.113005, Google ScholarCrossref
  16. 16. Y. Sakuraba, M. Ueda, Y. Miura, K. Sato, S. Bosu, K. Saito, M. Shirai, T. J. Konno, and K. Takanashi, Appl. Phys. Lett. 101, 252408 (2012). https://doi.org/10.1063/1.4772546, Google ScholarScitation, ISI
  17. 17. J. Bass and W. P. Pratt, Jr., J. Magn. Magn. Mater. 200, 274 (1999). https://doi.org/10.1016/S0304-8853(99)00316-9, Google ScholarCrossref
  18. 18. J. Bass and W. P. Pratt, Jr., J. Phys.: Condens. Matter 19, 183201 (2007). https://doi.org/10.1088/0953-8984/19/18/183201, Google ScholarCrossref
  19. 19. H.-K. Kim, M.-S. Yi, and S.-N. Lee, Thin Solid Films 517, 4039 (2009). https://doi.org/10.1016/j.tsf.2009.01.148, Google ScholarCrossref
  20. 20. A. M. H. R. Hakimi, N. Baberjee, A. Aziz, J. W. A. Robinson, and M. G. Blamire, Appl. Phys. Lett. 96, 102514 (2010). https://doi.org/10.1063/1.3339882, Google ScholarScitation
  21. 21. T. Minami, T. Kakumu, and S. Takata, J. Vac. Sci. Technol., A 14, 1704 (1996). https://doi.org/10.1116/1.580323, Google ScholarCrossref, ISI
  22. 22. H. Takatsuji, S. Tsuji, K. Kuroda, and H. Saka, Mater. Trans. 40, 899 (1999). https://doi.org/10.2320/matertrans1989.40.899, Google ScholarCrossref
  23. 23. Y. S. Jung, J. Y. Seo, D. W. Lee, and D. Y. Jeon, Thin Solid Films 445, 63 (2003). https://doi.org/10.1016/j.tsf.2003.09.014, Google ScholarCrossref
  24. 24. N. Ito, Y. Sato, P. K. Song, A. Kaijo, K. Inoue, and Y. Shigesato, Thin Solid Films 496, 99 (2006). https://doi.org/10.1016/j.tsf.2005.08.257, Google ScholarCrossref
  25. 25. Y. Kamiguchi, K. Saito, H. Iwasaki, M. Sahashi, M. Ouse, and S. Nakamura, J. Appl. Phys. 79, 6399 (1996). https://doi.org/10.1063/1.362011, Google ScholarScitation
  26. 26. H. Katada, K. Nakamoto, H. Hoshiya, K. Hoshino, N. Yoshida, M. Shiimoto, Y. Sato, H. Takazawa, K. Yasui, M. Hatatani, K. Watanabe, Y. Ikeda, and K. Meguro, J. Magn. Magn. Mater. 320, 2975 (2008). https://doi.org/10.1016/j.jmmm.2008.08.023, Google ScholarCrossref
  27. 27. Y. Sato, K. Hoshino, S. Okamura, K. Kato, and H. Hoshiya, IEEE Trans. Magn. 46, 1610 (2010). https://doi.org/10.1109/TMAG.2010.2045480, Google ScholarCrossref
  28. 28. H. Fukuzawa, H. Yuasa, K. Koi, H. Iwasaki, Y. Tanaka, Y. K. Takahashi, and K. Hono, J. Appl. Phys. 97, 10C509 (2005). https://doi.org/10.1063/1.1851673, Google ScholarScitation
  29. 29. H. Fukuzawa, H. Yuasa, and H. Iwasaki, J. Phys. D: Appl. Phys. 40, 1213 (2007). https://doi.org/10.1088/0022-3727/40/5/S01, Google ScholarCrossref
  30. 30. J. Sato, K. Matsushita, and H. Imamura, IEEE Trans. Magn. 44, 2608 (2008). https://doi.org/10.1109/TMAG.2008.2002507, Google ScholarCrossref
  31. © 2015 AIP Publishing LLC.