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:
Oct. 02, 2007
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 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