The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Jul. 08, 2008
Filed:
Sep. 30, 2004
Joseph P. Koetas, Landenberg, PA (US);
Alan E. Leviton, Newburyport, MA (US);
Kari-ell Norton, Holtwood, PA (US);
Samuel J. November, Newtown, PA (US);
Malcolm W. Robertson, Aston, PA (US);
Alan H. Saikin, Landenberg, PA (US);
Joseph P. Koetas, Landenberg, PA (US);
Alan E. Leviton, Newburyport, MA (US);
Kari-Ell Norton, Holtwood, PA (US);
Samuel J. November, Newtown, PA (US);
Malcolm W. Robertson, Aston, PA (US);
Alan H. Saikin, Landenberg, PA (US);
Rohm and Haas Electronic Materials CMP Holdings, Inc., Newark, DE (US);
Abstract
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.