Strong perpendicular magnetic anisotropy in thick CoFeB films sandwiched by Pd and MgO layers

A strong perpendicular magnetic anisotropy is formed in unit structures containing a thick CoFeB layer (2 nm) that are suitable for an MgO-based magnetic tunnel junction. The value of the coercivity, measured under perpendicular applied magnetic fields, is as high as 1050 Oe after annealing under optimum conditions. The intermixing between the Pd and the CoFeB and a low saturation magnetization of the Co-rich CoFeB layer are considered to be responsible for the strong perpendicular magnetic anisotropy.