Polishing pad of a chemical mechanical polishing apparatus and method of manufacturing the same

Abstract

The surface(s) of a polishing pad for polishing an object has a first portion including hydrophilic material and a second portion including hydrophobic material. The first portion of the polishing surface is located in a first region of the polishing pad and the second portion of the polishing surface is located in a second region of the polishing pad juxtaposed with the first region in the radial direction of the pad. The hydrophilic material may be a polymer resin that contains hydrophilic functional groups having OH and/or ═O at bonding sites of the polymer. The hydrophobic material may be a polymer resin that contains hydrophobic functional groups having H and/or F at bonding sites of the polymer. The polishing pad is manufactured by extruding respective lines of the hydrophilic and hydrophobic materials. The extruders and a backing are moved relative to each other such that the lines form concentric rings of the hydrophilic and hydrophobic materials.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

The above and other objects, features and advantages of the present invention will become more apparent from the following detailed description of the preferred embodiments thereof made with reference to the accompanying drawings, in which:

FIG. 1 is cross-sectional view of a conventional polishing pad and platen of a CMP apparatus;

FIG. 2A is a schematic diagram of an apparatus for use in manufacturing conventional polishing pads;

FIG. 2B is a perspective view of a product made using the apparatus of FIG. 2A and from which product conventional polishing pads are made;

FIG. 2C is a perspective view of conventional polishing pads produced form the product shown in FIG. 2B;

FIG. 3 is a graph illustrating ideal rates at which various regions of an object should be polished using the polishing pad shown in FIG. 1;

FIG. 4 is a graph illustrating actual rates at which various regions of a metal layer on a substrate are polished using the polishing pad shown in FIG. 1;

FIG. 5 is a graph illustrating actual rates at which various regions of an oxide layer on a substrate are polished using the polishing pad shown in FIG. 1;

FIG. 6 is a plan view of an embodiment of a polishing pad for use in a CMP apparatus according to the present invention;

FIG. 7 is a plan view of a second embodiment of a polishing pad for use in a CMP apparatus according to the present invention;

FIG. 8 is a cross-sectional view of the second embodiment of a polishing pad according to the present invention, illustrating the distribution of slurry on the polishing pad during a CMP process; and

FIG. 9 is an explanatory diagram illustrating a method of manufacturing a polishing pad according to the present invention.

Claims

1. A polishing pad for polishing an object, the polishing pad having opposite major surfaces, at least one of the major surfaces being a polishing surface, and the polishing surface having a first portion including hydrophilic material, and a second portion including hydrophobic material.

2. The polishing pad of claim 1, wherein the first and second portions of the polishing surface are located in respective regions of the pad that are juxtaposed in a radial direction of the pad.

3. The polishing pad of claim 2, wherein the first portion of the polishing surface is located in a peripheral region of the polishing pad and the second portion of the polishing surface is located in central region of the polishing pad.

4. The polishing pad of claim 2, wherein the first portion of the polishing surface is located in a central region of the polishing pad and the second portion of the polishing surface is located in a peripheral region of the polishing pad.

5. The polishing pad of claim 1, wherein the hydrophilic material comprises a polymer resin that includes hydrophilic functional groups having OH and/or ═O at bonding sites of the polymer.

6. The polishing pad of claim 5, wherein the hydrophilic material comprises at least one material selected from the group consisting of polyethylene glycol (PEG), polyvinyl alcohol (PVA), polyvinyl acetate (PVAC), unsaturated polyester resin and polyurethane.

7. The polishing pad of claim 1, wherein the hydrophobic material comprises a polymer resin that includes hydrophobic functional groups having H and/or F at bonding sites of the polymer.

8. The polishing pad of claim 1, wherein the hydrophobic material comprises at least one material selected from the group consisting of polycarbonate, polyethylene terephthalate glycol, polypropylene, diallylglycol carbonate, polyurethane and polybutadiene.

9. The polishing pad of claim 1, wherein the polishing surface comprises concavities and convexities.

10. The polishing pad of claim 1, wherein the density of the hydrophilic material of the first portion of the polishing surface is higher at one region thereof closer to the center of the polishing pad than at another region thereof closer to the periphery of the polishing pad, and the density of the hydrophobic material of the second portion of the polishing surface is higher at one region thereof closer to the periphery of the pad than at another region thereof closer to the center of the polishing pad.

11. The polishing pad of claim 10, wherein the first portion of the polishing surface is located in a peripheral region of the polishing pad and the second portion of the polishing surface is located in central region of the polishing pad.

12. The polishing pad of claim 1, wherein the density of the hydrophobic material of the second portion of the polishing surface is higher at a one region thereof located closer to the center of the polishing pad than at another region thereof located closer to the periphery of the polishing pad, and the density of the hydrophilic material of the first portion of the polishing surface is higher at one region thereof closer to the periphery of the polishing pad than at another region thereof located closer to the center of the polishing pad.

13. The polishing pad of claim 12, wherein the first portion of the polishing surface is located in a central region of the polishing pad and the second portion of the polishing surface is located in a peripheral region of the polishing pad.

14. A method of manufacturing a polishing pad, comprising: extruding hydrophilic material onto a first area of a backing; andextruding hydrophobic material onto a second area of the backing.

15. The method of claim 14, wherein the extruding of hydrophilic material comprises extruding a polymer resin that includes hydrophilic functional groups having OH and/or ═O at bonding sites of the polymer.

16. The method of claim 14, wherein the extruding of hydrophobic material comprises extruding a polymer resin that includes hydrophobic functional groups having H and/or F at bonding sites of the polymer.

17. The method of claim 14, further comprising thermally treating the hydrophilic material and the hydrophobic material.

18. The method of claim 14, further comprising cutting concavities into a surface constituted by the hydrophilic material and the hydrophobic material.

19. The method of claim 14, wherein the extruding of the hydrophilic material comprises forming a ring of the hydrophilic material.

20. The method of claim 14, wherein the extruding of the hydrophobic material comprises forming a ring of the hydrophobic material.

21. The method of claim 14, wherein the extruding of the hydrophilic material and hydrophobic materials comprises forming concentric rings of the hydrophilic and hydrophobic materials.