Patent ID: 7125318

Claim:
A polishing pad useful for polishing a surface of a semiconductor substrate, the polishing pad comprising: (a) a rotational axis; (b) a polishing layer that includes: (i) a central region; (ii) an outer peripheral edge spaced from the central region; and (iii) a generally annular polishing region configured to polish the surface of a workpiece and having an inner periphery adjacent the central region and an outer periphery spaced from the inner periphery; (c) a first plurality of grooves in the polishing layer, each groove of the first plurality of grooves having a first end located within the central region and a second end located within the polishing region, the second end being radially inward of the outer peripheral edge and radially outward of the rotational axis; and (d) a second plurality of grooves in the polishing layer, each groove of the second plurality of grooves spaced from ones of the first plurality of grooves and having a first end located within the polishing region and a second end located radially outward of the second end of the first plurality of grooves in at least one of: (i) the outer peripheral edge; and (ii) radially outward from the outer periphery of the polishing region.