Method of depositing a tantalum nitride/tantalum diffusion barrier layer system

US7253109B2 · kind B2 · utility

Assignee

• Applied Materials, Inc. · US

Inventors

• Peijun Ding · San Jose, US
• Zheng Xu · Hangzhou City, CN
• Hong Mei Zhang · Beijing, CN
• Xianmin Tang · San Jose, US
• Praburam Gopalraja · San Jose, US
• Suraj Rengarajan · Sunnyvale, US
• John C. Forster · San Francisco, US
• Jianming Fu · San Jose, US
• Tony P. Chiang · Campbell, US
• Gongda Yao · Fremont, US
• Fusen Chen · Dallas, US
• Barry Chin · Sunnyvale, US
• Gene Y. Kohara · Fremont, US

Key dates

• Filing date: Feb 28, 2005
• Grant date: Aug 7, 2007
• Expiry date: Feb 28, 2025

Classification

• Technology area (CPC H): Electricity
• CPC primary: H01L2924/0002
• WIPO field: Semiconductors
• WIPO sector: Electrical engineering

Abstract

We have discovered a method of providing a thin, approximately from about 2 Å to about 100 Å thick TaN seed layer, which can be used to induce the formation of alpha tantalum when tantalum is deposited over the TaN seed layer. Further, the TaN seed layer exhibits low resistivity, in the range of 30 μΩcm and can be used as a low resistivity barrier layer in the absence of an alpha tantalum layer. In one embodiment of the method, a TaN film is altered on its surface to form the TaN seed layer. In another embodiment of the method, a Ta film is altered on its surface to form the TaN seed layer.