Magnetic tunnel junction device and method of manufacturing the same

A half product of a magnetoresistive device comprising:

• a first amorphous ferromagnetic material layer;
• a tunnel barrier layer comprising a poly-crystalline magnesium oxide layer in which (001) crystal plane is preferentially oriented and which magnesium oxide layer has oxygen vacancy defects;
• and
• a second amorphous ferromagnetic material layer.

A magnetoresistive device having a magnetic tunnel junction structure comprising:

• a first ferromagnetic material layer of the BCC structure;
• a tunnel barrier layer;
• and
• a second ferromagnetic material layer of the BCC structure;
• wherein the tunnel barrier layer comprises a poly-crystalline magnesium oxide layer in which (001) crystal plane is preferentially oriented,
• the magnesium oxide layer has oxygen vacancy defects,
• a magnetoresistance ratio of the device is more than 70%, and
• an output voltage of the device is more than 200 mV.

A magnetic multilayer film comprising:

• a first ferromagnetic material layer;
• a poly-crystalline magnesium oxide layer in which (001) crystal plane is preferentially oriented, the magnesium oxide layer having oxygen vacancy defects;
• a second ferromagnetic material layer;
• and
• the first and second ferromagnetic material layers comprising Fe or a Fe-based alloy of the BCC structure and comprising a poly-crystalline layer in which (001) crystal plane is preferentially oriented.