Magnetic tunnel junction element and method for manufacturing same

A method for manufacturing a magnetic tunnel junction element,

• the magnetic tunnel junction element configured by stacking, in a following stack order,
• an underlayer formed of a metal material,
• a fixed layer formed of a ferromagnetic body,
• a magnetic coupling layer formed of a nonmagnetic body,
• a reference layer formed of a ferromagnetic body,
• a barrier layer formed of a nonmagnetic body, and
• a recording layer formed of a ferromagnetic body,
• or alternatively, the magnetic tunnel junction element configured by stacking, in a following stack order,
• a recording layer formed of a ferromagnetic body,
• a barrier layer formed of a nonmagnetic body,
• a reference layer formed of a ferromagnetic body,
• a magnetic coupling layer formed of a nonmagnetic body,
• an underlayer formed of a metal material, and
• a fixed layer formed of a ferromagnetic body,
• wherein a magnetization direction of the fixed layer, the reference layer and the recording layer is perpendicular to a film surface, and
• the fixed layer is formed and stacked after removing 1 nm or more of a surface of the formed underlayer by sputter etching, and
• wherein at least one of argon (Ar), krypton (Kr) and xenon (Xe) is used for the sputter etching, and
• wherein the sputter etching causes enough amount of at least one of argon (Ar), krypton (Kr) and xenon (Xe) to be contained at an area of the underlayer in contact with the fixed layer so that a crystal lattice spacing of the underlayer is varied.