Method to create air gaps using non-plasma processes to damage ILD materials

US7531444B2 · kind B2 · utility

Assignee

• International Business Machines Corporation · US

Inventors

• Christos D. Dimitrakopoulos · Baldwin Place, US
• Daniel C. Edelstein · White Plains, US
• Vincent J. McGahay · Poughkeepsie, US
• Satyanarayana V. Nittta · Poughquag, US
• Kevin S. Petrarca · Newburgh, US
• Shom Ponoth · Irvine, US
• Shahab Siddiqui · Clifton Park, US

Key dates

• Filing date: Feb 11, 2005
• Grant date: May 12, 2009
• Expiry date: Mar 26, 2026

Classification

• Technology area (CPC H): Electricity
• CPC primary: H01L21/76834
• WIPO field: Semiconductors
• WIPO sector: Electrical engineering

Abstract

A method of forming airgaps is provided where a blocking mask is applied to a substrate to shield a portion of the substrate from a beam of energy. After irradiation, the blocking mask is removed and a capping material is applied to the substrate. Alternatively, the capping material may be applied before irradiation. The capping material is perforated to allow an etchant to pass therethrough to the substrate below the capping material. The exposed portions of the substrate are removed from underneath the capping material by etching. The capping material is then sealed leaving sealed airgaps within the substrate.