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Selectable Resistance-Area Product by Dilute Highly Charged Ion Irradiation



Joshua M. Pomeroy, Holger Grube, A C. Perrella, John D. Gillaspy


In order to provide high performance read heads for future hard drive densities, considerable effort worldwide has been invested in developing techniques for producing low resistance area product (RA) magnetic tunnel junction sensors. In this letter, we present a method of producing tunnel junction barriers with a selectable RA value spanning more than three orders of magnitude from a single process recipe using highly charged ion (HCI) irradiation. The HCI irradiation occurs after formation of a plasma oxidized aluminum tunnel barrier. The neutralization of the highly charged ion on the tunnel barrier surface (Xe44+) ablates a small local volume, providing a enhanced conduction pathway that reduces the overall RA product. The final RA product is selected by appropriate choice of the HCI density, e.g. 100 HCIs/mm2 typically results in the RA product being reduced by a factor of 100.
Applied Physics Letters


highly charged ions, nanofeature, resistance-area product, tunnel junction


Pomeroy, J. , Grube, H. , Perrella, A. and Gillaspy, J. (2007), Selectable Resistance-Area Product by Dilute Highly Charged Ion Irradiation, Applied Physics Letters (Accessed April 22, 2024)
Created August 13, 2007, Updated February 17, 2017