Patent ID: 8062103

Claim:
A polishing pad useful for polishing at least one of a magnetic, optical and semiconductor substrate in the presence of a polishing medium with a polishing pad, the polishing pad comprising: a center, an inner region surrounding the center, a transition region connecting grooves from the inner region to an outer region surrounding the inner region, the outer region having multiple grooves, the multiple grooves having a high-rate path, at least fifty percent of the high-rate path being within twenty percent of a groove trajectory φ(r) in polar coordinates referenced to the concentric center of the polishing pad and defined in terms of (1) the distance R between the concentric center of the polishing pad and the rotational center of the substrate being polished, (2) the radius R c of the carrier fixture, and (3) the local angle θ c0 of grooves in the carrier fixture, defined with a groove equation as follows: ϕ ⁡ ( r ) = ∫ R - R C r ⁢ R R C ⁢ sin ⁢ ⁢ ϕ c + ( tan ⁢ ⁢ θ c ⁢ ⁢ 0 ) ⁢ ( R R C ⁢ cos ⁢ ⁢ ϕ c + 1 ) ( R R C ⁢ cos ⁢ ⁢ ϕ c + 1 ) - ( tan ⁢ ⁢ θ c ⁢ ⁢ 0 ) ⁢ R R C ⁢ sin ⁢ ⁢ ϕ c ⁢ ⁢ ⅆ r ′ r ′ where ϕ c = cos - 1 ( R 2 + R C 2 - r 2 2 ⁢ RR C ) - π for ⁢ ⁢ values ⁢ ⁢ of ⁢ ⁢ r ⁢ ⁢ from ⁢ ⁢ ( R - R C ) ⁢ ⁢ to ⁢ ⁢ ( R + R C ) the transition region being adjacent the outer region and within a radius from the center defined as follows: r TR = 0.7 ⁢ r * ⁢ ⁢ to ⁢ ⁢ 1.3 ⁢ r * where r * = R C ⁢ ( R R C ⁢ ) 2 - cos ⁡ ( 2 ⁢ θ c ⁢ ⁢ 0 ) - sin ⁢ ⁢ ( 2 ⁢ ⁢ θ c ⁢ ⁢ 0 ) ⁢ ( R / R C cos ⁢ ⁢ θ c ⁢ ⁢ 0 ) 2 - 1 ; and wherein the inner region originates continuous grooves that extend uninterrupted to the outer region.