International Business Machines Corporation

Robert Albin Jurjevic

Cuc Kim Huynh

Matthew J Rutten

James Albert Gilhooly

Douglas P Nadeau

Richard John Lebel

Susan L Cohen

Matthew Kilpatrick Miller

Disclosed is an improved apparatus and method for polishing a semiconductor wafer, which involves mounting the wafer to a carrier assembly. The wafer carrier assembly has been split into two plates which are joined by springs around the peripheries. The wafer carrier assembly is universally mounted on a rotation shaft which rotates the wafer carrier assembly during cleaning. An adjustment screw tilts the upper plate relative to the lower plate. The adjustment screw can be located at any predetermined point on a circle around the rotation shaft. Since the bottom plate is forced relatively flat by contact with a polishing pad, the net effect of the wafer carrier assembly is to apply increased pressure to the wafer edge under the screw. This provides for an even polishing action to compensate for otherwise non-uniform radial polishing action on the wafer surface.

Flexible tilted wafer carrier

A method for cleaning the surface of a semiconductor wafer by removing residual slurry particles adhered to the wafer surface after chemical-mechanical polishing is provided. The semiconductor wafer is subjected to a first polishing step using a basic aqueous solution of a nonionic polymeric surfactant comprising alkylphenoxypolyethoxyethanol, preferably nonylphenoxypolyethoxyethanol, at a concentration between about 30 to about 100 ppm and a quaternary ammonium hydroxide such as TMAH at a concentration between about 2.5% and about 6% by weight. A downforce of between about 0 and 2 psi (1.4.times.10.sup.5 dynes/cm.sup.2) is applied for at least 15 seconds. A second polishing step with an applied downforce of at least 4 psi is then employed while applying purified water. The method provides at least a ten fold reduction in the number of submicronic slurry particles remaining on the wafer surface and can be completed within a commercially acceptable amount of time. In addition, particles as small as 0.007 .mu.m can be removed. The method also provides a level of accuracy in the predictability of the number of residual particles remaining on the wafer surface.

Process for removing residue from a semiconductor wafer after

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Williston, VT, United States of America

Robert Albin Jurjevic