Rohm and Haas Electronic Materials Cmp Holdings, Inc.

Malcolm W Robertson

Alan Saikin

Samuel J November

Alan E Leviton

Kari-Ell Norton

Joseph P Koetas

The present invention provides a method of forming a chemical mechanical polishing pad, comprising providing a tank with polymeric materials and providing a storage hopper with microspheres having an initial bulk density, wherein the storage hopper further comprises a porous membrane provided over a plenum. The method further provides the steps of connecting a fluidizing gas source to the plenum through a gas inlet line and fluidizing the microspheres and reducing the initial bulk density by feeding gas into the plenum. In addition, the method further provides the steps of providing a delivery system for delivering the polymeric materials and the microspheres to a mixer, forming a mixture of the polymeric materials and the microspheres, pouring the mixture into a mold to form a molded product and cutting the molded product into the polishing pad.

Method of forming a polishing pad having reduced striations

The present invention provides an apparatusfor forming a striation-reduced chemical mechanical polishing pad. The polishing padcomprises a first delivery linefor delivering a polymeric materialinto a mixerand a second delivery linefor delivering microspheresinto the mixerwith the polymeric material. The second delivery lineis connected to a bulk density control unit. The bulk density control unitcomprises a storage hopperfor storing the microspheres. The storage hopperfurther comprises a porous membraneprovided over a plenum. A fluidizing gas sourceis connected to the plenumthrough a gas inlet line. Gasfed into the plenumfrom the fluidizing gas sourcepermeates through the porous membraneand reduces the initial bulk density of the microspheresin the storage hopper

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Aston, PA, United States of America

Malcolm W Robertson