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.
Type:
Grant
Filed:
May 17, 2013
Date of Patent:
November 11, 2014
Assignees:
Intermoecular, Inc., Kabushiki Kaisha Toshiba, SanDisk 3D LLC
Inventors:
Yun Wang, Tony P. Chiang, Vidyut Gopal, Imran Hashim, Dipankar Pramanik