Method of forming a polishing pad with reduced stress window

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.