Chemical mechanical polishing pad having holes and or grooves
Disclosed is a chemical mechanical polishing pad formed with holes, grooves or a combination thereof. The chemical mechanical polishing pad is characterized in that a plurality of concentric circles each having grooves, holes, or a combination thereof are formed at a polishing surface of the polishing pad. The chemical mechanical polishing pad provides effects of effectively controlling a flow of slurry during a polishing process, thereby achieving a stability in the polishing process in terms of a polishing rate, and achieving an enhancement in the planarization of a wafer.
1. A chemical mechanical polishing pad for use in a chemical mechanical polishing process, wherein a plurality of concentric circles each having grooves, holes, or a combination thereof are formed at a polishing surface of the pad, and the concentric circles are non-uniformly spaced apart from one another so that the space defined between adjacent ones of the concentric circles is gradually reduced from a central portion of the pad to a peripheral portion of the pad.
2. The chemical mechanical polishing pad according to claim 1 , wherein each of the concentric circles has a plurality of discontinuous grooves arranged to be spaced apart from one another, each of the grooves having a desired depth, a desired width, and a desired length.
3. The chemical mechanical polishing pad according to claim 2 , wherein the grooves are different in at least one of their depth, width, and length.
4. The chemical mechanical polishing pad according to claim 1 , wherein the grooves, holes, or combination thereof are machined by a laser.
5. The chemical mechanical polishing pad according to claim 1 , wherein each of the concentric circles has a plurality of holes arranged to be spaced apart from one another, each of the holes having a desired depth and a desired diameter.
6. The chemical mechanical polishing pad according to claim 5 , wherein the holes are different in respect of at least one dimension selected from the group consisting of their depth and and diameter, and the holes of at least one concentric circle are arranged so that the space between adjacent holes is different from other spaces in the same concentric circle.
7. The chemical mechanical polishing pad according to claim 1 , wherein each of the concentric circles has a combination of holes having a desired depth, a desired diameter, and a desired space defined between adjacent ones thereof and grooves having a desired depth, a desired width, and a desired length, the holes and grooves being alternately arranged while being spaced apart from one another to alternate at least one of the holes with one of the grooves.