Abstract: The present invention provides a chemical mechanical polishing pad having reduced stress windows. In addition, the present invention provides a method of forming a chemical mechanical polishing pad, the method comprising, primary annealing a window separate from a polishing pad material and providing the polishing pad material in a periphery of the primary annealed window before a predetermined quench temperature of the primary annealed window. The method further comprises secondary annealing the window and the polishing pad material together and cutting the secondary annealed window and the polishing pad material to a predetermined thickness.

Abstract: A method of fabricating a polishing pad in which a pad material includes a polishing layer overlying a substantially optically transparent backing layer is subjected to a process in which an optical window is formed in the pad material by removing a portion of the polishing layer and exposing an underlying portion of the substantially optically transparent backing layer. Prior to forming the optical window, the polishing layer is bonded to the backing layer to form a sealed interface, then a portion of the polishing layer is mechanically cut away from the backing layers. Since the backing layer is not pierced during the removal process, a liquid, such as an aqueous polishing slurry, cannot leak through the optical window and on to underlying portions of a polishing apparatus to which the pad material is mounted.

Abstract: A method of fabricating a polishing pad in which a pad material includes a polishing layer overlying a substantially optically transparent backing layer is subjected to a process in which an optical window is formed in the pad material by removing a portion of the polishing layer and exposing an underlying portion of the substantially optically transparent backing layer. Prior to forming the optical window, the polishing layer is bonded to the backing layer to form a sealed interface, then a portion of the polishing layer is mechanically cut away from the backing layers. Since the backing layer is not pierced during the removal process, a liquid, such as an aqueous polishing slurry, cannot leak through the optical window and on to underlying portions of a polishing apparatus to which the pad material is mounted.