Highly scalable STT-MRAM with MTJs of top-pinned structure in 1T/1MTJ cell

Abstract

We report on spin transfer torque magnetoresistance random access memory (STT-MRAM) with magnetic tunnel junctions (MTJs) that have a top-pinned stacking structure. By adopting the top-pinned structure, in which a pinned layer and an antiferromagnetic layer are deposited above the MgO tunnel barrier, we can relieve the current limitation caused by driving power asymmetry of the transistor in a 1T/1M structure without an additional current path to make a reverse connection between the transistor and the top side of the MTJs, resulting in the cell area being reduced by about half.