Patent · US Active

Magnetic random access memory devices including multi-bit cells

US8576615B2 · kind B2 · utility

3Cited by
29References
20Claims
0Family size

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Key dates

Filing dateJun 10, 2011
Grant dateNov 5, 2013
Priority date
Expiry dateJan 13, 2032

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG11C11/1675
  • WIPO fieldComputer technology
  • WIPO sectorElectrical engineering

Abstract

A magnetic random access memory (“MRAM”) cell includes: (1) a first magnetic layer having a first magnetization direction and a magnetic anisotropy axis; (2) a second magnetic layer having a second magnetization direction; and (3) a spacer layer disposed between the first magnetic layer and the second magnetic layer. The MRAM cell also includes a field line magnetically coupled to the MRAM cell and configured to induce a write magnetic field along a magnetic field axis, and the magnetic anisotropy axis is tilted relative to the magnetic field axis. During a write operation, the first magnetization direction is switchable between m directions to store data corresponding to one of m logic states, with m>2, at least one of the m directions is aligned relative to the magnetic anisotropy axis, and at least another one of the m directions is aligned relative to the magnetic field axis.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.