Perpendicular magnetic tunnel junction (pMTJ) devices employing a thin pinned layer stack and providing a transitioning start to a body-centered cubic (BCC) crystalline / amorphous structure below an upper anti-parallel (AP) layer
US9590010B1 · kind B1 · utility
Assignee
Inventors
Key dates
| Filing date | Mar 24, 2016 |
| Grant date | Mar 7, 2017 |
| Priority date | — |
| Expiry date | Mar 24, 2036 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH10N50/85
- WIPO fieldComputer technology
- WIPO sectorElectrical engineering
Abstract
Perpendicular magnetic tunnel junction (pMTJ) devices employing a pinned layer stack with a thin top anti-parallel (AP2) layer and having a transitioning layer providing a transitioning start to a body-centered cubic (BCC) crystalline/amorphous structure below the top anti-parallel (AP2) layer, to promote a high tunnel magnetoresistance ratio (TMR) with reduced pinned layer thickness are disclosed. A first anti-parallel (AP) ferromagnetic (AP1) layer in a pinned layer has a face-centered cubic (FCC) or hexagonal closed packed (HCP) crystalline structure. A transitioning material (e.g., Iron (Fe)) is provided in a transitioning layer between the AP1 layer and an AFC layer (e.g., Chromium (Cr)) that starts a transition from a FCC or HCP crystalline structure, to a BCC crystalline/amorphous structure. In this manner, a second AP ferromagnetic (AP2) layer disposed on the AFC layer can be provided in a reduced thickness BCC crystalline or amorphous structure to provide a high TMR with a reduced pinned layer thickness.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.