Patent · US Expired

Magnetic random access memory with stacked toggle memory cells

US6937497B1 · kind B1 · utility

27Cited by
4References
39Claims
0Family size

Assignee

Inventors

Key dates

Filing dateNov 18, 2004
Grant dateAug 30, 2005
Priority date
Expiry dateNov 18, 2024

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG11C11/16
  • WIPO fieldComputer technology
  • WIPO sectorElectrical engineering

Abstract

A “toggling” type of magnetic random access memory (MRAM) has memory stacks arranged in the X-Y plane on the MRAM substrate with each memory stack having a plurality of toggle memory cells stacked along the Z axis. Each memory stack is located at an intersection region between two orthogonal write lines. Each cell in the stack is a “toggle” cell that has its synthetic antiferromagnet (SAF) free layer easy axis of magnetization aligned nonparallel with the X and Y axes and angularly spaced about the Z axis from the easy axes of magnetization of all the other SAF free layers in the stack. Each cell in a stack is magnetically separated from adjacent cells in the stack by a nonmagnetic separation layer. The magnetization direction of the free layer in a selected memory cell in a stack can be switched without switching the magnetization directions of the free layers in the other memory cells in the stack.

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