Patent ID: 7108597

Claim:
A rotary polishing pad rotatable about a rotational axis suitable for polishing at least one of magnetic, optical and semiconductor substrates, comprising: (a) a polishing layer having a polishing region defined by a first boundary corresponding to a trajectory of a first point on the polishing pad and a second boundary defined by a trajectory of a second point on the polishing pad, the second boundary being spaced from the first boundary, a first zone proximate the second boundary, a second zone between the second boundary and the first boundary, and a third zone proximate the first boundary; (b) a plurality of first small-angle grooves at least partially contained within the polishing region proximate the first boundary and forming an angle of −40° to 40° relative to the first boundary at a point proximate the first boundary and in the third zone; (c) a plurality of second small-angle grooves at least partially contained within the polishing region proximate the second boundary and forming an angle of −40° to 40° relative to the second boundary at a point proximate the second boundary and in the first zone; and (d) a plurality of large-angle grooves, each contained within the polishing region and located between the plurality of first small-angle grooves and the plurality of second small angle grooves and each of the plurality of large-angle grooves forming an angle of 45° to 135° relative to each of the first boundary and the second boundary, and in the second zone and wherein the plurality of first small-angle grooves connect to a corresponding one of the plurality of large-angle grooves and the plurality of large-angle grooves connects to a corresponding one of a second plurality of small-angle grooves.