Patent ID: 7799689

Claim:
A chemical mechanical polishing (CMP) method for polishing a workpiece, comprising: performing a first CMP of the workpiece to remove a portion of a metal on the workpiece, the first CMP characterized by chemical factors and mechanical factors; adjusting at least one of the mechanical or chemical factors to increase a polishing effect of the mechanical factors relative to the chemical factors; and performing, following the adjusting, a second CMP of the workpiece to further remove the metal on the workpiece, the first and second CMP removing the metal without substantially removing an adjacent insulating material, wherein: the chemical factors associated with the first CMP are collectively defined as C bulk , the mechanical factors associated with the first CMP are collectively defined as M bulk , the chemical factors associated with a second CMP are collectively defined as C end , the mechanical factors associated with a second CMP are collectively defined as M end , M end and C end are chosen such that M end /C end >M bulk /C bulk , the first CMP of the workpiece is performed in accordance with M bulk and C bulk , and the second CMP of the workpiece is performed in accordance with M end and C end .