Process for forming a damascene structure

US6649531B2 · kind B2 · utility

Assignee

• International Business Machines Corporation · US

Inventors

• William J. Cote · Poughquag, US
• Timothy J. Dalton · Ridgefield, US
• Prakash Dev · Plano, US
• Daniel C. Edelstein · White Plains, US
• Scott D. Halle · Slingerlands, US
• Gill Yong Lee · San Jose, US
• Arpan Mahorowala · West Linn, US

Key dates

• Filing date: Nov 26, 2001
• Grant date: Nov 18, 2003
• Expiry date: Dec 17, 2021

Classification

• Technology area (CPC H): Electricity
• CPC primary: H01L21/02274
• WIPO field: Semiconductors
• WIPO sector: Electrical engineering

Abstract

A process for forming a damascene structure includes depositing a bilayer comprising a first dielectric layer and a second dielectric layer onto a substrate, wherein the first layer has a dielectric constant higher than the second layer, and wherein the second layer is selected from a low k dielectric material comprising Si, C, O and H. The multi-step damascene structure is patterned into the dielectric bilayer using highly selective anisotropic reactive ion etching. Photoresist, polymers and post etch residues are removed from the substrate using a plasma ashing process without damaging the underlying dielectric layers.