Polishing pad having polishing surface with continuous protrusions
View Patent ↗Polishing pads having a polishing surface with continuous protrusions are described. Methods of fabricating polishing pads having a polishing surface with continuous protrusions are also described.
1. A polishing pad for polishing a substrate, the polishing pad comprising:
a polishing body having a polishing side opposite a back surface;
a polishing surface comprising a plurality of cylindrical protrusions continuous with the polishing side of the polishing body, wherein the plurality of cylindrical protrusions is arranged in a hexagonal-packed pattern; and
a solid ring encompassing the plurality of cylindrical protrusions at an outer most edge of the polishing side of the polishing body, the solid ring continuous with the polishing side of the polishing body and having an inner shape that follows a contour of the hexagonal-packed pattern of the plurality of cylindrical protrusions, wherein the hexagonal-packed pattern of the plurality of cylindrical protrusions is interrupted by a plurality of grooves within the solid ring.
2. The polishing pad of claim 1 , wherein the each of the plurality of cylindrical protrusions has a shape in a plane of the polishing surface that is selected from the group consisting of a circle, an oval, a triangle, and a polygon having five or more sides.
3. The polishing pad of claim 1 ,
wherein the hexagonal-packed pattern of the plurality of cylindrical protrusions terminates proximate to the ring in a staggered arrangement.
4. The polishing pad of claim 1 , further comprising:
a button region disposed centrally within the hexagonal-packed pattern of the plurality of cylindrical protrusions, the button region having a hexagonal shape.
5. The polishing pad of claim 4 , wherein the button region further comprises a triangular clocking mark on one side of the hexagonal shape.
6. The polishing pad of claim 1 , wherein the plurality of cylindrical protrusions is arranged in a plurality of high density regions having less spacing between adjacent protrusions within a high density region than between adjacent protrusions of adjacent high density regions.
7. The polishing pad of claim 1 , wherein each of the plurality of cylindrical protrusions has a maximum lateral dimension approximately in the range of 1-30 millimeters, with a spacing between one another approximately in the range of 0.1-3 millimeters.
8. The polishing pad of claim 1 , wherein each cylindrical protrusion of a first portion of the plurality of cylindrical protrusions has a first maximum lateral dimension, and each cylindrical protrusion of a second portion of the plurality of cylindrical protrusions has a second, different, maximum lateral dimension.
9. The polishing pad of claim 8 , wherein a pattern of the plurality of cylindrical protrusions comprises a cylindrical protrusion having a maximum lateral dimension of approximately 10 millimeters surrounded by a plurality of cylindrical protrusions each having a maximum lateral dimension of approximately 1 millimeter.
10. The polishing pad of claim 1 , wherein each cylindrical protrusion of a first portion of the plurality of cylindrical protrusions has a first shape in a plane of the polishing surface, and each cylindrical protrusion of a second portion of the plurality of cylindrical protrusions has a second, different, shape in the plane of the polishing surface.
11. The polishing pad of claim 1 , wherein the total surface area of the plurality of cylindrical protrusions is a portion approximately in the range of 40-80% of the total surface area of the polishing side of the polishing body.
12. The polishing pad of claim 1 , wherein the height of each of the plurality of cylindrical protrusions is approximately in the range of 0.5-1 millimeter.
13. The polishing pad of claim 1 , wherein the plurality of cylindrical protrusions comprises approximately between 50,000-200,000 protrusions for a polishing pad having a diameter approximately in the range of 29-32 inches.
14. The polishing pad of claim 1 , wherein each cylindrical protrusion of a first portion of the plurality of cylindrical protrusions has a first height from the polishing body, and each cylindrical protrusion of a second portion of the plurality of cylindrical protrusions has a second, different, height from the polishing body, but all of the plurality of cylindrical protrusions are substantially co-planar distal from the polishing body.
15. The polishing pad of claim 1 , wherein the polishing body and polishing surface are together homogeneous and unitary.
16. The polishing pad of claim 15 , wherein the polishing body and polishing surface comprise a molded polyurethane material.
17. The polishing pad of claim 16 , wherein the molded polyurethane material has a pore density of closed cell pores approximately in the range of 6%-50% total void volume.
18. The polishing pad of claim 1 , further comprising:
a foundation layer disposed on the back surface of the polishing body.
19. The polishing pad of claim 1 , further comprising:
a detection region disposed in the back surface of the polishing body.
20. The polishing pad of claim 1 , further comprising:
an aperture disposed in the polishing surface and polishing body; and
an adhesive sheet disposed on the back surface of the polishing body, the adhesive sheet providing an impermeable seal for the aperture at the back surface of the polishing body.
21. The polishing pad of claim 1 , further comprising:
a sub pad disposed on the back surface of the polishing body.
22. The polishing pad of claim 1 , further comprising:
a local area transparency (LAT) region disposed in the polishing body, the LAT region interrupting a pattern of the plurality of cylindrical protrusions.