Structural dependence of the tunnel magnetoresistance for magnetic tunnel junctions with a full-Heusler [Co.sub.2]Fe(Al, Si) electrode

The crystal structure and magnetic moment of the [Co.sub.2]FeAl and [Co.sub.2]FeSi films deposited onto thermally oxidized Si and MgO(100) single-crystal substrates are investigated, along with the structural effect on the tunnel magnetoresistance (TMR) of the magnetic tunnel junctions using [Co.sub.2]FeZ (Z=Al or Si). The substrate and post annealing temperatures, changed the structure, in which the fully epitaxial and polycrystalline [Co.sub.2]FeAl and [Co.sub.2]FeSi films were obtained with different disorder structure.