Copper has replaced aluminum as the main interconnect material due to its low resistivity and high electromigration resistance.It is the most promising candidate for next generation technology provided the associated patterning problems are solved satisfactorily.One possible approach for the integration of copper technology into the device manufacturing process is by using dual damascene technique in which chemical mechanical polishing (CMP) is employed to remove overburden material and planarize the surface for further processing.CMP is one of the important processes in the fabrication of integrated circuits (IC).