Process for electroless copper deposition

US7651934B2 · kind B2 · utility

Assignee

• Applied Materials, Inc. · US

Inventors

• Dmitry Lubomirsky · Cupertino, US
• Timothy Weidman · Sunnyvale, US
• Arulkumar Shanmugasundram · Sunnyvale, US
• Nicolay Kovarsky · Sunnyvale, US
• Kapila Wijekoon · Santa Clara, US

Key dates

• Filing date: Mar 20, 2006
• Grant date: Jan 26, 2010
• Expiry date: Apr 24, 2028

Classification

• Technology area (CPC H): Electricity
• CPC primary: H01L21/76874
• WIPO field: Surface technology, coating
• WIPO sector: Chemistry

Abstract

Embodiments of the invention provide methods for forming conductive materials within contact features on a substrate by depositing a seed layer within a feature and subsequently filling the feature with a copper-containing material during an electroless deposition process. In one example, a copper electroless deposition solution contains levelers to form convexed or concaved copper surfaces. In another example, a seed layer is selectively deposited on the bottom surface of the aperture while leaving the sidewalls substantially free of the seed material during a collimated PVD process. In another example, the seed layer is conformably deposited by a PVD process and subsequently, a portion of the seed layer and the underlayer are plasma etched to expose an underlying contact surface. In another example, a ruthenium seed layer is formed on an exposed contact surface by an ALD process utilizing the chemical precursor ruthenium tetroxide.