US Patent 11289644 Magnetic tunnel junction having all-around structure

A magnetic tunnel junction (MTJ) device includes a cylindrically-shaped pillar structure and a first ferromagnetic layer disposed on at least a portion of the pillar structure. The first ferromagnetic layer exhibits a magnetization that is changeable in the presence of at least one of an applied bias and heat. The MTJ device further includes a dielectric barrier disposed on at least a portion of the first ferromagnetic layer and a second ferromagnetic layer disposed on at least a portion of the dielectric barrier. The second ferromagnetic layer exhibits a magnetization that is fixed. The MTJ device is configured such that the first and second ferromagnetic layers and the dielectric barrier concentrically surround the pillar structure.