Magnetic tunnel junctions with B2 -ordered Co2 FeAl full Heusler alloy as a ferromagnetic electrode were fabricated by sputtering on thermally oxidized Si/ SiO2 amorphous substrates. A Co2 FeAl/MgO/ Co50 Fe50 structure showed a highly (001)-textured structure and the tunneling magnetoresistance (TMR) ratio of 166% at room temperature and 252% at 48 K were achieved. The temperature dependence of TMR can be fitted with spin wave excitation model, and the bias voltage dependence of differential conductance demonstrated that the high TMR was mainly contributed by coherent tunneling. This work suggests the B2 -Co2 FeAl is one of the promising candidates for practical spintronic applications.
ASJC Scopus subject areas
- Physics and Astronomy (miscellaneous)