Self aligned via and pillar cut for at least a self aligned double pitch

US9548243B1 · kind B1 · utility

Assignee

• International Business Machines Corporation · US

Inventors

• Benjamin D. Briggs · Cohoes, US
• Lawrence A. Clevenger · Saratoga Springs, US
• Michael Rizzolo · Delmar, US
• Terry A. Spooner · Clifton Park, US
• Theodorus E. Standaert · Clifton Park, US

Key dates

• Filing date: Jun 30, 2015
• Grant date: Jan 17, 2017
• Expiry date: Jun 30, 2035

Classification

• Technology area (CPC H): Electricity
• CPC primary: H01L23/5329
• WIPO field: Semiconductors
• WIPO sector: Electrical engineering

Abstract

A method of forming via openings that includes forming sidewall spacers on a plurality of mandrels that are overlying a hardmask layer that is present on an interlevel dielectric layer. Etching the hardmask layer using a portion of the sidewall spacers and the plurality of mandrels to form a first pillar of hardmask material. The interlevel dielectric layer is etched using the first pillar of hardmask material as a mask to define a first via opening. The plurality of mandrels are removed. The hardmask layer is etched using the spacers to define a second pillar of hardmask material. The interlevel dielectric layer is etched using the second pillar of hardmask material to provide a second via opening.