Figure 5

Dependence of f.c.c. crystallinity of the MgO tunneling barrier and MgO capping layer on thickness of Fe diffusion barrier for double MgO-based p-MTJ spin-valves with top Co2Fe6B2 free layer. (a) p-MTJ spin-valve without Fe diffusion barrier, (b) p-MTJ spin-valve with 0.30-nm-thick Fe diffusion barrier, and (c) p-MTJ spin-valve with 0.66-nm-thick Fe diffusion barrier. Cross-sectional high-resolution TEM images were observed at 200 keV in acceleration voltage.