Article Metrics


Online attention

In-situ grazing incidence X-ray diffraction measurements of relaxation in Fe/MgO/Fe epitaxial magnetic tunnel junctions during annealing

DOI: 10.1016/j.jmmm.2013.08.018 DOI Help

Authors: D. S. Eastwood (Durham University) , M. Ali (University of Leeds) , B. J. Hickey (University of Leeds) , B. K. Tanner (University of Durham)
Co-authored by industrial partner: No

Type: Journal Paper
Journal: Journal Of Magnetism And Magnetic Materials

State: Published (Approved)
Published: August 2013

Abstract: The relaxation of Fe/MgO/Fe tunnel junctions grown epitaxially on (001) MgO substrates has been measured by in-situ grazing incidence in-plane X-ray diffraction during the thermal annealing cycle. We find that the Fe layers are fully relaxed and that there are no irreversible changes during annealing. The MgO tunnel barrier is initially strained towards the Fe but on annealing, relaxes and expands towards the bulk MgO value. The strain dispersion is reduced in the MgO by about 40% above 480 K post-annealing. There is no significant change in the “twist” mosaic. Our results indicate that the final annealing stage of device fabrication, crucial to attainment of high TMR, induces substantial strain relaxation at the MgO barrier/lower Fe electrode interface.

Journal Keywords: Grazing Incidence In-Plane X-Ray Diffraction; Epitaxial Magnetic Tunnel Junction; Lattice Relaxation

Subject Areas: Physics, Materials, Engineering

Instruments: I16-Materials and Magnetism