Device, system and method for improved magnetic anisotropy of a magnetic tunnel junction

• Main Authors: Maertz, Brian, Doczy, Mark L, Doyle, Brian S, Brockman, Justin S, Golonzka, Oleg, Ghani, Tahir, Bergstrom, Daniel B, Wiegand, Christopher J, Ouellette, Daniel G, O'Brien, Kevin P, Oguz, Kaan, Rahman, MD Tofizur
• Format: Patent
• Language: English
• Published: 13.10.2020
• Subjects: BASIC ELECTRIC ELEMENTS; ELECTRIC SOLID STATE DEVICES NOT OTHERWISE PROVIDED FOR; ELECTRICITY; INFORMATION STORAGE; PHYSICS; SEMICONDUCTOR DEVICES; STATIC STORES

Material layer stack structures to provide a magnetic tunnel junction (MTJ) having improved perpendicular magnetic anisotropy (PMA) characteristics. In an embodiment, a free magnetic layer of the material layer stack is disposed between a tunnel barrier layer and a cap layer of magnesium oxide (Mg). The free magnetic layer includes a Cobalt-Iron-Boron (CoFeB) body substantially comprised of a combination of Cobalt atoms, Iron atoms and Boron atoms. A first Boron mass fraction of the CoFeB body is equal to or more than 25% (e.g., equal to or more than 27%) in a first region which adjoins an interface of the free magnetic layer with the tunnel barrier layer. In another embodiment, the first Boron mass fraction is more than a second Boron mass fraction in a second region of the CoFeB body which adjoins an interface of the free magnetic layer with the cap layer.