Spin valves using insulating cobalt ferrite exchange-spring pinning layers

Cobalt ferrite, CoFe2O4, thin films are explored as pinning layers for read sensor applications. High ΔR/R values, 12.8%, and high pinning fields, 1500 Oe, are observed. Unlike other coercivity based pinning layers, the soft properties of the free layer are not compromised. The properties of the cobalt ferrite layers are strongly dependent on the microstructure, which, in turn, depends on the reactive sputtering process. © 2002 American Institute of Physics.