We fabricated fully epitaxial Fe/MgAl2O4/Fe (001) magnetic tunnel junctions using plasma oxidation of an Mg/Al bilayer. The MgAl2O4 showed a (001)-oriented spinel-type structure, and there were few misfit dislocations at the interfaces between the MgAl 2O4 and the two Fe layers due to a small lattice mismatch (∼1%). Tunnel magnetoresistance (TMR) ratios up to 117% (165%) were obtained at room temperature (15 K). The bias voltage for one-half of the zero-bias TMR ratio (Vhalf) was relatively large, ranging from 1.0 to 1.3 V at room temperature, which is attributed to the small misfit dislocation density.
ASJC Scopus subject areas
- Physics and Astronomy (miscellaneous)