The Role of Preoxidation on the Interface Structure of Co/MgO Multilayers

It has previously been reported that preoxidation of the bottom electrode prior to deposition of the Al ₂ O ₃ or MgO barrier in magnetic tunnel junctions acts to suppress orange-peel coupling between Co electrodes. Here, we present specular and diffuse X-ray scattering measurements from Co/MgO multilayer repeat structures which suggest that this drop arises from a reduction in the in-plane correlation length of the roughness at the electrode-barrier interface rather than reduction in roughness amplitude.