Magnetic random access memory with thermally stable magnetic tunnel junction cells
US6518588B1 · kind B1 · utility
Assignee
Inventors
Key dates
| Filing date | Oct 17, 2001 |
| Grant date | Feb 11, 2003 |
| Priority date | — |
| Expiry date | Oct 17, 2021 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH10N50/85
- WIPO fieldMicro-structural and nano-technology
- WIPO sectorChemistry
Abstract
A magnetic tunnel junction (MTJ) memory cell and a magnetic random access memory (MRAM) incorporating the cells has upper and lower cell electrodes that are formed of bilayers that provide electrical connection between the cells and the copper word and bit lines of the MRAM. The bilayers are formed of a first layer of tantalum nitride or tungsten nitride and a second layer of tantalum or tungsten. In one embodiment TaN is formed directly on the copper and low-resistivity alpha-Ta is formed directly on the TaN. If the cells use an antiferromagnetic layer to fix the moment of the pinned ferromagnetic layer, then Pt—Mn is the preferred material formed over the alpha-Ta. The bilayer can function as a lateral electrode to connect a horizontally spaced-apart cell and a copper stud in the MRAM.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.