CMP wafer carrier for preferential polishing of a wafer

US5885135A · kind A · utility

Assignee

• International Business Machines Corporation · US

Inventors

• Daniel D. Desorcie · Enosburg Falls, US
• Richard J. Lebel · Williston, US
• Charles A. McKinney · Chazy, US
• Rock Nadeau · Jericho, US
• Timothy J. Rickard, Jr. · Colchester, US
• Paul Smith · Fort Collins, US
• Douglas K. Sturtevant · South Burlington, US
• Matthew T. Tiersch · South Burlington, US

Key dates

• Filing date: Apr 23, 1997
• Grant date: Mar 23, 1999
• Expiry date: Apr 23, 2017

Classification

• Technology area (CPC H): Electricity
• CPC primary: H01L21/302
• WIPO field: Machine tools
• WIPO sector: Mechanical engineering

Abstract

An apparatus for polishing a semiconductor wafer is provided which includes a wafer carrier having on its lower surface a non-uniform surface structure means to vary the force against a wafer during a polishing operation so that the polishing is enhanced and imparts a planar surface across the polished wafer. Preferred non-uniform surface structure means include use of a wafer carrier having on its lower surface a backing film having a first central portion having a predetermined compressibility and a second peripheral portion having a different compressibility than the first portion. Another non-uniform surface structure means to vary the force against the wafer comprises a wafer carrier having on its lower surface a raised circumferential region around the periphery of the carrier.