Interconnect structures and methods of making thereof

US7365001B2 · kind B2 · utility

Assignee

• International Business Machines Corporation · US

Inventors

• Chih-Chao Yang · Glenmont, US
• Louis L. Hsu · Fishkill, US
• Keith Kwong Hon Wong · Wappingers Falls, US
• Timothy J. Dalton · Ridgefield, US
• Carl Radens · Lagrangeville, US
• Larry Clevenger · Lagrangeville, US

Key dates

• Filing date: Dec 16, 2003
• Grant date: Apr 29, 2008
• Expiry date: Apr 15, 2025

Classification

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

Abstract

A method of making a diffusion barrier for a interconnect structure. The method comprises: providing a conductive line in a bottom dielectric trench; depositing a sacrificial liner on the cap layer; depositing an interlayer dielectric; forming a trench and a via in the top interlayer dielectric; and removing a portion of the cap layer and the sacrificial layer proximate to the bottom surface of the via. The removed portions of the cap layer and sacrificial layer deposit predominantly along the lower sidewalls of the via. The conductive line is in contact with a cap layer, and the sacrificial layer is in contact with the cap layer. The invention is also directed to the interconnect structures resulting from the inventive process.