Method for writing to a random access memory (MRAM) cell with improved MRAM cell lifespan
US9396782B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Jun 7, 2013 |
| Grant date | Jul 19, 2016 |
| Priority date | — |
| Expiry date | Jun 7, 2033 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG11C11/161
- WIPO fieldComputer technology
- WIPO sectorElectrical engineering
Abstract
Method for writing to a MRAM cell including a magnetic tunnel junction including a first and second ferromagnetic layer, and a tunnel barrier layer; and a bipolar transistor in electrical connection with one end of the magnetic tunnel junction, the bipolar transistor being arranged for controlling the passing and polarity of a heating current in the magnetic tunnel junction. The method includes a sequence of writing steps, each writing step including passing the heating current in the magnetic tunnel junction such as to heat it to a high temperature threshold; and once the magnetic tunnel junction has reached the high temperature threshold, adjusting a second magnetization of the second ferromagnetic layer for writing a write data; wherein during one of the writing steps, the polarity of the heating current is reversed from one during the subsequent writing step. The method allows for an increased lifespan of the MRAM cell.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.