Patent ID: 10950660

Abstract:
A perpendicular spin transfer torque memory (pSTTM) device incorporates a magnetic tunnel junction (MTJ) device having a free magnetic stack and a fixed magnetic stack separated by a dielectric tunneling layer. The free magnetic stack includes an uppermost magnetic layer that is at least partially covered by a cap layer. The cap layer is at least partially covered by a protective layer containing at least one of: ruthenium (Ru); cobalt/iron/boron (CoFeB); molybdenum (Mo); cobalt (Co); tungsten (W); or platinum (Pt). The protective layer is at least partially covered by a cap metal layer which may form a portion of MTJ electrode. The protective layer minimizes the occurrence of physical and/or chemical attack of the cap layer by the materials used in the cap metal layer, beneficially improving the interface anisotropy of the MTJ free magnetic layer.