Abstract

The demagnetizing field of a Co50Fe50 free layer in an in-plane micron-sized magnetic tunnel junction (MTJ) can be partially compensated by exchange coupling with a [Co90Fe10/Pt] N multilayer with perpendicular magnetic anisotropy via a Ru interlayer. The perpendicular anisotropy for N = 5 is optimized for nominal CoFe and Pt thickness of 0.4 nm and 1.0 nm, respectively. An increase of tunnel magnetoresistance (TMR) from 2% to 75% is observed in MTJs as the free layer thickness, t varies from 1.0 nm to 3.0 nm. A phenomenological model is developed to interpret the TMR dependence in terms of the free layer magnetization rotation from in-plane to out-of-plane with decreasing t, a consequence of interlayer exchange coupling with the perpendicular multilayer. We suggest that this strategy could significantly reduce the switching current density in such MTJs.

Full Text
Published version (Free)

Talk to us

Join us for a 30 min session where you can share your feedback and ask us any queries you have

Schedule a call