Method of making toroidal MRAM cells
US6936479B2 · kind B2 · utility
Assignee
Inventor
Key dates
| Filing date | Jan 15, 2004 |
| Grant date | Aug 30, 2005 |
| Priority date | — |
| Expiry date | Feb 21, 2024 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG11C11/16
- WIPO fieldComputer technology
- WIPO sectorElectrical engineering
Abstract
This invention provides a method of making nano-scaled toroidal magnetic memory cells, such as may be used, for example, in magnetic random access memory (MRAM). In a particular embodiment a semiconductor wafer substrate is prepared and a conductor layer is provided upon the wafer. A hard layer is deposited upon the first conductor. From the hard layer, ion etching is employed to form an annular wall about a pillar, the wall and pillar defining an annular slot. A ferromagnetic data layer is deposited within the annular slot and a junction stack is then provided upon at least a portion of the data layer. A dielectric is applied to insulate the structure and then planarized to expose the pillar.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.