Patent ID: 9446497
Filing Date: 2016-09-20
CPC Classification: B24B

Claim Text:
1. A multilayer chemical mechanical polishing pad for polishing a substrate selected from at least one of a magnetic substrate, an optical substrate and a semiconductor substrate; comprising: a polishing layer having a polishing surface, a counterbore opening, an outer perimeter, a polishing layer interfacial region parallel to the polishing surface and an average non-interfacial region thickness, T a porous subpad layer having a bottom surface, an outer perimeter and a porous subpad layer interfacial region parallel to the bottom surface; a pressure sensitive adhesive layer; and, a broad spectrum, endpoint detection window block having a thickness, T wherein the broad spectrum, endpoint detection window block, consists of a monophase olefin copolymer; wherein the olefin copolymer is a random copolymer of: wherein the broad spectrum, endpoint detection window block exhibits a uniform chemical composition across its thickness, T wherein the polishing layer interfacial region and the porous subpad layer interfacial region form a coextensive region; wherein the coextensive region secures the polishing layer to the porous subpad layer without the use of a laminating adhesive; wherein the pressure sensitive adhesive layer is applied to the bottom surface of the porous subpad layer; wherein the multilayer chemical mechanical polishing pad has a through opening that extends from the polishing surface to the bottom surface of the porous subpad layer; wherein the counterbore opening opens on the polishing surface, enlarges the through opening and forms a ledge; wherein the ledge is parallel to the polishing surface; wherein the counterbore opening has an average depth, D wherein the average depth, D wherein the broad spectrum, endpoint detection window block is disposed within the counterbore opening on the ledge; wherein the broad spectrum, endpoint detection window block is bonded to the polishing layer; and, wherein the polishing surface is adapted for polishing the substrate.