Hostname: page-component-cd9895bd7-fscjk Total loading time: 0 Render date: 2024-12-27T02:07:27.272Z Has data issue: false hasContentIssue false
  • English
  • Français

Highly Charged Ion Modified Magnetic Tunnel Junctions

Published online by Cambridge University Press:  01 February 2011

Holger Grube ,
J. M. Pomeroy ,
A. C. Perrella  and
J. D. Gillaspy
Holger Grube
Affiliation:
[email protected], National Institute of Standards and Technology, Atomic Physics, 100 Bureau Drive, Mail Stop 8423, Gaithersburg, MD, 20899, United States, 301 975-4609
J. M. Pomeroy
Affiliation:
[email protected], National Institute of Standards and Technology, 100 Bureau Drive, Mail Stop 8423, Gaithersburg, MD, 20899, United States
A. C. Perrella
Affiliation:
[email protected], National Institute of Standards and Technology, 100 Bureau Drive, Mail Stop 8423, Gaithersburg, MD, 20899, United States
J. D. Gillaspy
Affiliation:
[email protected], National Institute of Standards and Technology, 100 Bureau Drive, Mail Stop 8423, Gaithersburg, MD, 20899, United States
Get access

Abstract

We have used highly charged ions (HCIs) such as Xe44+ to modify ultrathin aluminum oxide barriers in magnetic tunnel junctions (MTJs) in order to controllably adjust their electrical properties independently of oxide thickness. We have reduced the resistance area (RA) product of our MTJ devices by up to three orders of magnitude down to our present measurement uncertainty limit of 30 Ω·μm2 by varying the HCI dose. Preliminary experiments indicate that HCI modified Co/Al2O3/Co MTJs have a reduced magnetoresistance (MR) of ≈ 1% at room temperature as compared to ≈ 10% for undosed devices. The goal of this effort is to fabricate a magnetic field sensor in current-perpendicular-to-plane (CPP) geometry with an RA optimized for hard drive read heads. This is an improvement over presently demonstrated CPP architectures based on giant magnetoresistance or tunnel junctions, whose RAs are either to low or too high.

Keywords

magnetoresistance (transport)thin filmion-solid interactions
Type
Research Article
Information
MRS Online Proceedings Library (OPL) , Volume 960: Symposium N – Self Assembly of Nanostructures Aided by Ion- or Photon-Beam Irradiation—Fundamentals and Applications , 2006 , 0960-N08-02
Copyright
Copyright © Materials Research Society 2007

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. Kuwashima, T., Fukuda, K., Kiyono, H., Sato, K., Kagami, T., Saruki, S., Uesugi, T., Kasahara, N., Ohta, N., Nagai, K., et al., “Electrical Performance and Reliability of Tunnel Magnetoresistance Heads for 100-Gb/in2 Application”, IEEE Trans. Magn. 40, 176 (2004).Google Scholar
2. Nagasaka, K., Seyama, Y., Varga, L., Shimizu, Y., and Tanaka, A., “Giant magnetoresistance properties of specular spin valve films in CPP structure,” J. Appl. Phys. 89, 6943 (2001).Google Scholar
3. Parkin, S. S. P., Li, Z. G., and Smith, David J., “Giant magnetoresistance in antiferromagnetic Co/Cu multilayers” Appl. Phys. Lett. 58 2710 (1991).Google Scholar
4. Moodera, J. S., Kinder, L. R., Wong, T. M., and Meservey, R., “Large magnetoresistance at room temperature in ferromagnetic thin film tunnel junctions”, Phys. Rev. Lett. 74, 3273 (1995).Google Scholar
5. Nagamine, Y., Maehara, H., Tsunekawa, K., Djayaprawira, D. D., Watanabe, N., Yuasa, S., and Ando, K., “Ultralow resistance-area product of 0.4 Ω (μm)2 and high magnetoresistance above 50% in CoFeB/MgO/CoFeB magnetic tunnel junctions”, Appl. Phys. Lett. 89, 162507 (2006).Google Scholar
6. Schenkel, T., Hamza, A. V., Barnes, A. V., and Schneider, D. H., “Interaction of slow, very highly charged ions with surfaces”, Prog. Surf. Sci. 61, 23 (1999).Google Scholar
7. Hayderer, G., Cernusca, S., Schmid, M., Varga, P., Winter, H. P., Aumayr, F., Niemann, D., Hoffmann, V., Stolterfoht, N., Lemell, C., Wirtz, L., and Burgdörfer, J., “Kinetically Assisted Potential Sputtering of Insulators by Highly Charged Ions”, Phys. Rev. Lett. 86, 3530 (2001).Google Scholar
8. Pomeroy, J. M., Grube, H., Perrella, A. C., and Gillaspy, J. D., Nuclear Instruments & Methods in Physics Research Section B-Beam Interactions with Materials and Atoms (accepted 2006).Google Scholar
9. Gillaspy, J., “Highly charged ions”, Journal of Physics B: At. Mol. Opt. Phys. 34 R93 (2001).Google Scholar
10. Pikin, A., Morgan, C., Bell, E., Ratliff, L., Gillaspy, J., “A beam line for highly charged ions”, Reviews of Scientific Instruments 67 2528 (1996).Google Scholar