Atomic layer deposition of metal oxide materials for memory applications
US8466446B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Sep 12, 2012 |
| Grant date | Jun 18, 2013 |
| Priority date | — |
| Expiry date | Sep 12, 2032 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH10B63/80
- WIPO fieldSemiconductors
- WIPO sectorElectrical engineering
Abstract
Embodiments of the invention generally relate to nonvolatile memory devices, such as a ReRAM cells, and methods for manufacturing such memory devices, which includes optimized, atomic layer deposition (ALD) processes for forming metal oxide film stacks. The metal oxide film stacks contain a metal oxide coupling layer disposed on a metal oxide host layer, each layer having different grain structures/sizes. The interface disposed between the metal oxide layers facilitates oxygen vacancy movement. In many examples, the interface is a misaligned grain interface containing numerous grain boundaries extending parallel to the electrode interfaces, in contrast to the grains in the bulk film extending perpendicular to the electrode interfaces. As a result, oxygen vacancies are trapped and released during switching without significant loss of vacancies. Therefore, the metal oxide film stacks have improved switching performance and reliability during memory cell applications compared to traditional hafnium oxide based stacks of previous memory cells.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.