Topography reduction and control by selective accelerator removal

US8470191B2 · kind B2 · utility

Assignee

• Novellus Systems, Inc. · US

Inventors

• Steven T. Mayer · Lake Oswego, US
• Mark L. Rea · Tigard, US
• Richard S. Hill · Atherton, US
• Avishai Kepten · Jerusalem, IL
• R. Marshall Stowell · Wilsonville, US
• Eric G. Webb · West Linn, US

Key dates

• Filing date: Aug 6, 2007
• Grant date: Jun 25, 2013
• Expiry date: Dec 6, 2030

Classification

• Technology area (CPC H): Electricity
• CPC primary: H01L21/76877
• WIPO field: Surface technology, coating
• WIPO sector: Chemistry

Abstract

Plating accelerator is applied selectively to a substantially-unfilled wide (e.g., low-aspect-ratio feature cavity. Then, plating of metal is conducted to fill the wide feature cavity and to form an embossed structure in which the height of a wide-feature metal protrusion over the metal-filled wide-feature cavity is higher than the height of metal over field regions. Most of the overburden metal is removed using non-contact techniques, such as chemical wet etching. Metal above the wide feature cavity protects the metal-filled wide-feature interconnect against dishing, and improved planarization techniques avoid erosion of the metal interconnect and dielectric insulating layer. In some embodiments, plating of metal onto a substrate is conducted to fill narrow (e.g., high-aspect-ratio feature cavities) in the dielectric layer before selective application of plating accelerator and filling of the wide feature cavity.