# US 10,319,903 B2 · Multiferroic magnetic tunnel junction devices > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 10,319,903 B2 - Document ID: US10319903B2 - Status: Granted - Kind: B2 - Application number: 15/364,153 - Filed: 2016-11-29 - Published: 2018-05-31 - Granted: 2019-06-11 - Earliest claimed: 2016-11-29 - Assignees: Micron Technology, Inc. - Applicants: Micron Technology, Inc. - Inventors: Sumeet C. Pandey - Web page: https://patentgrep.com/patent/US10319903B2 ## CPC - H10N 50/85: Materials of the active region - H10B 61/00: Magnetic memory devices, e.g. magnetoresistive RAM [MRAM] devices - H10N 39/00: Integrated devices, or assemblies of multiple devices, comprising at least one piezoelectric, electrostrictive or magnetostrictive element covered by groups H10N30/00 – H10N35/00 - H10N 50/10: Magnetoresistive devices - H10N 59/00: Integrated devices, or assemblies of multiple devices, comprising at least one galvanomagnetic or Hall-effect element covered by groups H10N50/00 - H10N52/00 (MRAM devices H10B61/00) - H10N: ELECTRIC SOLID-STATE DEVICES NOT OTHERWISE PROVIDED FOR - H10B: ELECTRONIC MEMORY DEVICES ## Abstract Some embodiments include a magnetic tunnel junction device having a first magnetic electrode, a second magnetic electrode, and a tunnel insulator material between the first and second magnetic electrodes. A tungsten-containing material is directly against one of the magnetic electrodes. In some embodiments the tungsten-containing material may be in a first crystalline lattice arrangement, and the directly adjacent magnetic electrode may be in a second crystalline lattice arrangement different from said first crystalline lattice arrangement. In some embodiments the tungsten-containing material, the first magnetic electrode, the tunnel insulator material and the second magnetic electrode all comprise a common crystalline lattice arrangement. ## Claims ### Claim 1 A magnetic tunnel junction device, comprising: a first magnetic electrode comprising a first composition comprising Fe and Co, a second magnetic electrode comprising a second composition comprising Fe and Co, and a tunnel insulator material between the first and second magnetic electrodes; and a tungsten-containing material directly against one of the magnetic electrodes, the tungsten-containing material further comprising one or both of Ru and Ir, wherein an elevationally lowest material of the magnetic tunnel junction device is one of the first composition comprising Fe and Co and the second composition comprising Fe and Co, the tungsten-containing material having a body-centered cubic crystalline lattice arrangement, and said one of the magnetic electrodes being in a face-centered cubic crystalline lattice arrangement. ### Claim 2 (depends on 1) The magnetic tunnel junction device of claim 1 being a multiferroic device. ### Claim 3 (depends on 1) The magnetic tunnel junction device of claim 1 being a magnetoelectric device. ### Claim 4 (depends on 1) The magnetic tunnel junction device of claim 1 having increased sensitivity of magnetic anisotropy to an applied electric-field/voltage due to separate or combined magnetoelastic and multiferroic effects. ### Claim 5 (depends on 1) The magnetic tunnel junction device of claim 1 wherein the tunnel insulator material is piezoelectric. ### Claim 6 (depends on 5) The magnetic tunnel junction device of claim 5 wherein the tunnel insulator material includes one or both of ferroelectric substances and antiferroelectric substances. ### Claim 7 (depends on 1) The magnetic tunnel junction device of claim 1 wherein the tunnel insulator material is not piezoelectric. ### Claim 8 (depends on 1) The magnetic tunnel junction device of claim 1 wherein the tunnel insulator material includes zirconium and oxygen, and includes one or more of Ba, Bi, Be, Ca, Mg, Hf, Al, S, Sr, Ti and Cr. ### Claim 9 A magnetic tunnel junction device, comprising: a stack of materials on an upper surface of a substrate, the stack of materials consisting of: a free magnetic electrode, a fixed magnetic electrode, and a tunnel insulator material between the free and fixed magnetic electrodes; and a tungsten-containing material directly against the fixed magnetic electrode; wherein the tungsten-containing material further comprises one or both of Ir and Ru and is in a body-centered crystalline lattice arrangement, and wherein the fixed magnetic electrode is in a face-centered crystalline lattice arrangement different from said first crystalline lattice arrangement. ### Claim 10 (depends on 9) The magnetic tunnel junction device of claim 9 being a multiferroic device. ### Claim 11 (depends on 9) The magnetic tunnel junction device of claim 9 being a magnetoelectric device. ### Claim 12 (depends on 9) The magnetic tunnel junction device of claim 9 wherein the body-centered crystalline lattice arrangement and the face-centered crystalline lattice arrangement are both cubic crystal systems. ### Claim 13 (depends on 9) The magnetic tunnel junction device of claim 9 wherein the tunnel insulator material includes zirconium and oxygen, and includes one or more of Ba, Bi, Be, Ca, Mg, Hf, Al, S, Sr, Ti and Cr. ### Claim 14 (depends on 9) The magnetic tunnel junction device of claim 9 wherein the tunnel insulator material is piezoelectric. ### Claim 15 (depends on 14) The magnetic tunnel junction device of claim 14 wherein the tunnel insulator material includes one or both of ferroelectric substances and antiferroelectric substances. ### Claim 16 (depends on 9) The magnetic tunnel junction device of claim 9 wherein the tunnel insulator material is not piezoelectric.