Magnetic tunnel junction (MTJ) devices with heterogeneous free layer structure, particularly suited for spin-torque-transfer (STT) magnetic random access memory (MRAM) (STT MRAM)
US10134808B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Apr 25, 2016 |
| Grant date | Nov 20, 2018 |
| Priority date | — |
| Expiry date | Apr 25, 2036 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH10N50/85
- WIPO fieldComputer technology
- WIPO sectorElectrical engineering
Abstract
Magnetic tunnel junction (MTJ) devices with a heterogeneous free layer structure particularly suited for efficient spin-torque-transfer (STT) magnetic random access memory (MRAM) (STT MRAM) are disclosed. In one aspect, a MTJ structure with a reduced thickness first pinned layer section provided below a first tunnel magneto-resistance (TMR) barrier layer is provided. The first pinned layer section includes one pinned layer magnetized in one magnetic orientation. In another aspect, a second pinned layer section and a second TMR barrier layer are provided above a free layer section and above the first TMR barrier layer in the MTJ. The second pinned layer is magnetized in a magnetic orientation that is anti-parallel (AP) to that of the first pinned layer section. In yet another aspect, the free layer comprises first and second heterogeneous layers separated by an anti-ferromagnetic coupling spacer, the first and second heterogeneous layers differing in their magnetic anisotropy.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.