Multi-step pre-clean for selective metal gap fill

US11776806B2 · kind B2 · utility

Assignee

• Applied Materials, Inc. · US

Inventors

• Xi Cen · San Jose, US
• Yakuan Yao · Campbell, US
• Yiming Lai · San Jose, US
• Kai Wu · Palo Alto, US
• Avgerinos V. Gelatos · Scotts Valley, US
• David T. Or · Santa Clara, US
• Kevin Kashefi · San Ramon, US
• Yu Lei · Belmont, US
• Lin Dong · Sunnyvale, US
• He Ren · San Jose, US
• Yi Xu · Singapore, SG
• Mehul Naik · San Jose, US
• Hao Chen · Ann Arbor, US
• Mang-Mang Ling · San Jose, US

Key dates

• Filing date: May 12, 2022
• Grant date: Oct 3, 2023
• Expiry date: May 12, 2042

Classification

• Technology area (CPC H): Electricity
• CPC primary: H01L21/76879
• WIPO field: Semiconductors
• WIPO sector: Electrical engineering

Abstract

Methods for pre-cleaning substrates having metal and dielectric surfaces are described. The substrate is exposed to a strong reductant to remove contaminants from the metal surface and damage the dielectric surface. The substrate is then exposed to an oxidation process to repair the damage to the dielectric surface and oxidize the metal surface. The substrate is then exposed to a weak reductant to reduce the metal oxide to a pure metal surface without substantially affecting the dielectric surface. Processing tools and computer readable media for practicing the method are also described.