Method for removing protuberances at the surface of a semiconductor wafer using a chem-mech polishing technique

US4671851A · kind A · utility

Assignee

• International Business Machines Corporation · US

Inventors

• Klaus D. Beyer · Poughkeepsie, US
• James S. Makris · Wappingers Falls, US
• Eric Mendel · Poughkeepsie, US
• Karen A. Nummy · Newburgh, US
• Seiki Ogura · Wappingers Falls, US
• Jacob Riseman · Poughkeepsie, US
• Nivo Rovedo · Lagrangeville, US

Key dates

• Filing date: Oct 28, 1985
• Grant date: Jun 9, 1987
• Expiry date: Oct 28, 2005

Classification

• Technology area (CPC H): Electricity
• CPC primary: H01L21/76202
• WIPO field: Semiconductors
• WIPO sector: Electrical engineering

Abstract

A chemical-mechanical (chem-mech) method for removing SiO.sub.2 protuberances at the surface of a silicon chip, such protuberances including "bird's heads". A thin etch stop layer of Si.sub.3 N.sub.4 is deposited onto the wafer surface, which is then chem-mech polished with a SiO.sub.2 water based slurry. The Si.sub.3 N.sub.4 acts as a polishing or etch stop barrier layer only on the planar portions of the wafer surface. The portions of the Si.sub.3 N.sub.4 layer located on the top and at the sidewalls of the "bird's heads" and the underlying SiO.sub.2 protuberances are removed to provide a substantially planar integrated structure.