Thermal Stability Of Magnetic Tunneling Junctions With Mgo Barriers For High Temperature Spintronics

Thermal stability of MgO-based magnetic tunnel junctions has been investigated from room temperature up to 500 degrees C, in both the memory and sensor configurations. Junctions showed magnetoresistances of over 200% at room temperature and over 100% at 300 degrees C. Below 375 degrees C, the resistance of the parallel state remains constant, while the antiparallel state resistance linearly decreases with temperature. Above that, a rapid increase in the resistance of both states was observed, along with an irreversible loss of magnetoresistance. Junctions in the sensor configuration exhibited a constant sensitivity of 1.0%/Oe at temperatures up to 300 degrees C before getting degraded. (c) 2006 American Institute of Physics.