Atomic layer deposition of hafnium and zirconium oxides for memory applications

US8546275B2 · kind B2 · utility

Assignees

• INTERMOLECULAR, INC. · US
• Kabushiki Kaisha Toshiba · JP
• SanDisk 3D LLC · US

Inventors

• Yun Wang · San Jose, US
• Vidyut Gopal · Sunnyvale, US
• Imran Hashim · Saratoga, US
• Dipankar Pramanik · Saratoga, US
• Tony P. Chiang · Campbell, US

Key dates

• Filing date: Sep 19, 2011
• Grant date: Oct 1, 2013
• Expiry date: Sep 19, 2031

Classification

• Technology area (CPC H): Electricity
• CPC primary: H10B63/80

Abstract

Embodiments of the invention generally relate to nonvolatile memory devices and methods for manufacturing such memory devices. The methods for forming improved memory devices, such as a ReRAM cells, provide optimized, atomic layer deposition (ALD) processes for forming a metal oxide film stack having a metal oxide buffer layer disposed on or over a metal oxide bulk layer. The metal oxide bulk layer contains a metal-rich oxide material and the metal oxide buffer layer contains a metal-poor oxide material. The metal oxide bulk layer is less electrically resistive than the metal oxide buffer layer since the metal oxide bulk layer is less oxidized or more metallic than the metal oxide buffer layer. In one example, the metal oxide bulk layer contains a metal-rich hafnium oxide material and the metal oxide buffer layer contains a metal-poor zirconium oxide material.