Magnetic random access memory with three or more stacked toggle memory cells and method for writing a selected cell
US6992910B1 · kind B1 · utility
Assignee
Inventors
Key dates
| Filing date | Jul 20, 2005 |
| Grant date | Jan 31, 2006 |
| Priority date | — |
| Expiry date | Aug 2, 2025 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH10B61/20
- 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.