Magnetic tunneling junction device, memory device including the same, and method of manufacturing the magnetic tunneling junction device

A memory device comprising:

• a plurality of memory cells, each of the plurality of memory cells comprising a magnetic tunneling junction device and a switching device connected to the magnetic tunneling junction device,
• wherein the magnetic tunneling junction device comprises,
• a first magnetic layer,
• a second magnetic layer facing the first magnetic layer, and
• an oxide layer disposed between the first magnetic layer and the second magnetic layer and comprising a metal oxide,
• wherein the metal oxide of the oxide layer has a stoichiometrically oxygen-deficient composition, and
• the second magnetic layer comprises a magnetic material doped with a metal element.

A manufacturing method of a magnetic tunneling junction device, the manufacturing method comprising:

• preparing an oxide layer comprising a metal oxide;
• cooling the oxide layer in a temperature range less than or equal to about 250 Kelvin (K);
• depositing a wetting layer comprising a magnetic material on the oxide layer;
• oxidizing or nitriding the wetting layer;
• depositing a magnetic layer comprising a magnetic material doped with a metal element on the wetting layer;
• and
• annealing the magnetic layer at a temperature greater than or equal to about 300 K, and
• wherein the metal oxide has a stoichiometrically oxygen-deficient composition.

A magnetic tunneling junction device comprising:

• a first magnetic layer;
• a second magnetic layer facing the first magnetic layer;
• and
• a first oxide layer between the first magnetic layer and the second magnetic layer and comprising a metal oxide,
• wherein the first oxide layer comprises a first region adjacent to the first magnetic layer and a second region adjacent to the second magnetic layer, and
• a proportion of a first element in the second region is greater than a proportion of the first element in the first region, the first element being oxygen or nitrogen.