Synthetic anti-ferromagnetic structure with non-magnetic spacer for MRAM applications
US7630232B2 · kind B2 · utility
Assignee
Inventor
Key dates
| Filing date | Sep 14, 2007 |
| Grant date | Dec 8, 2009 |
| Priority date | — |
| Expiry date | Dec 24, 2027 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH10N50/10
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
A toggle MTJ cell is disclosed that has a nearly balanced SAF free layer with two major sub-layers separated by an anti-parallel coupling layer. Within each major sub-layer, there is a plurality of minor sub-layers wherein adjacent minor sub-layers are separated by a parallel coupling layer. The parallel coupling layer is a non-magnetic layer that may be a one or more of Ta, Cu, Cr, Ru, Os, Re, Rh, Nb, Mo, W, Ir, and V, a metal oxide, or dusting of NiCr, Ta, Cu, or NiFeCr. Magnetic moments of major sub-layers are made to be nearly equal so that the net moment of the SAF free layer is essentially zero. The MTJ cell and SAF free layer preferably have an aspect ratio of from 1 to 5. Ferromagnetic coupling between minor sub-layers enables a lower write current and lower power consumption than conventional toggle cell designs.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.