Multilevel phase change memory
US7488968B2 · kind B2 · utility
Assignee
Inventor
Key dates
| Filing date | May 5, 2005 |
| Grant date | Feb 10, 2009 |
| Priority date | — |
| Expiry date | Jun 11, 2025 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH10N70/882
- WIPO fieldComputer technology
- WIPO sectorElectrical engineering
Abstract
A multilevel phase change memory may be formed of a chalcogenide material formed between a pair of spaced electrodes. The cross-sectional area of the chalcogenide material may decrease as the material extends from one electrode to another. As a result, the current density decreases from one electrode to the other. This means that a higher current is necessary to convert the material that has the largest cross-sectional area. As a result, different current levels may be utilized to convert different amounts of the chalcogenide material to the amorphous or reset state. A distinguishable resistance may be associated with each of those different amounts of amorphous material, providing the opportunity to engineer a number of different current selectable programmable states.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.