POLISHING PADS AND SYSTEMS AND METHODS OF MAKING AND USING THE SAME

• US 20170182629A1
• Filed: 03/31/2015
• Published: 06/29/2017
• Est. Priority Date: 04/03/2014
• Status: Active Grant

• Current Assignee: 3M Innovative Properties Company (3M Company)
• Original Assignee: 3M Innovative Properties Company (3M Company)
• Inventors: David, Moses M., Lehuu, Duy K., Meyer, Kenneth A.P.
• Granted Patent: US 10,071,461 B2
• Time in Patent Office: Days
• CPC Class Codes: B24B 37/22 characterised by a multi-layered structure
• CPC Class Codes: B24B 37/24 characterised by the composition or properties of the pad materials
• CPC Class Codes: B24B 37/245 Pads with fixed abrasives
• CPC Class Codes: B24B 37/26 characterised by the shape of the lapping pad surface, e.g. grooved
• CPC Class Codes: B24B 7/228 for grinding thin, brittle parts, e.g. semiconductors, wafers grinding edges of thin, brittle parts B24B9/065
• CPC Class Codes: B24B 7/241 Methods

Abstract

The present disclosure relates to polishing pads which include a polishing layer, wherein the polishing layer includes a working surface and a second surface opposite the working surface. The working surface includes a plurality of precisely shaped pores, a plurality of precisely shaped asperities and a land region. The present disclosure further relates to a polishing system, the polishing system includes the preceding polishing pad and a polishing solution. The present disclosure relates to a method of polishing a substrate, the method of polishing including: providing a polishing pad according to any one of the previous polishing pads; providing a substrate, contacting the working surface of the polishing pad with the substrate surface, moving the polishing pad and the substrate relative to one another while maintaining contact between the working surface of the polishing pad and the substrate surface, wherein polishing is conducted in the presence of a polishing solution.

Claims

1. ) A polishing pad comprising a polishing layer having a working surface and a second surface opposite the working surface;

wherein the working surface includes a plurality of precisely shaped pores, a plurality of precisely shaped asperities and a land region;

wherein each pore has a pore opening, each asperity has an asperity base, and a plurality of the asperity bases are substantially coplanar relative to at least one adjacent pore opening;

wherein the depth of the plurality of precisely shaped pores is less than the thickness of the land region adjacent to each precisely shaped pore and the thickness of the land region is less than about 5 mm; and

wherein the polishing layer comprises a polymer.

2. ) The polishing pad of claim 1, wherein the height of at least about 10% of the plurality of precisely shaped asperities is between about 1 micron and about 200 microns.

3. ) The polishing pad of claim 1, wherein the depth of at least about 10% of the plurality of precisely shaped pores is between about 1 micron and about 200 microns.

4. ) The polishing pad of claim 1, wherein the areal density of the plurality of precisely shaped asperities is independent of the areal density of the plurality precisely shaped pores.

5. ) The polishing pad of claim 1, wherein the polishing layer further comprises a polymer, wherein the polymer includes including thermoplastics, thermoplastic elastomers (TPEs), thermosets and combinations thereof.

6. ) The polishing pad of claim 5, wherein the polymer includes a thermoplastic or thermoplastic elastomer.

7. ) The polishing pad of claim 6, wherein the thermoplastic and thermoplastic elastomer include polyurethanes, polyalkylenes, polybutadiene, polyisoprene, polyalkylene oxides, polyesters, polyamides, polycarbonates, polystyrenes, block copolymers of any of the proceeding polymers, and combinations thereof.

8. ) The polishing pad of claim 1, wherein the polishing layer is free of through-holes.

9. ) The polishing pad of claim 1, wherein the polishing layer is a unitary sheet.

10. ) The polishing pad of claim 1, wherein the polishing layer contains less than 1% by volume inorganic abrasive particles.

11. ) The polishing pad of claim 1, wherein the precisely shaped asperities are solid structures.

12. ) The polishing pad of claim 1, wherein the precisely shaped asperities are free of machined holes.

13. ) The polishing pad of claim 1, wherein, the polishing layer is flexible and capable of being bent back upon itself producing a radius of curvature in the bend region of between about 10 cm and about 0.1 mm.

14. ) The polishing pad of claim 1, wherein the ratio of the surface area of the distal ends of the precisely shaped asperities to the projected polishing pad surface area is between about 0.0001 and about 4.

15. ) The polishing pad of claim 1, wherein the ratio of the surface area of the distal ends of the precisely shaped asperities to the surface area of the precisely shaped pore openings is between about 0.0001 and about 4.

16. ) The polishing pad of claim 1, further comprising at least one macro-channel.

17. ) The polishing pad of claim 16, wherein the depth of at least a portion of the plurality of precisely shaped pores is less than the depth of at least a portion of the at least one macro-channel.

18. ) The polishing pad of claim 16, wherein the width of at least a portion of the plurality of precisely shaped pores is less than the width of at least a portion of the at least one macro-channel.

19. ) The polishing pad of claim 16, wherein the ratio of the depth of at least a portion of the at least one macro-channel to the depth of a portion of the precisely shaped pores is between about 1.5 and about 1000.

20. ) The polishing pad of claim 16, wherein the ratio of the width of at least a portion of the at least one macro-channel to the width of a portion of the precisely shaped pores is between about 1.5 and about 1000.

21. ) The polishing pad of claim 1, wherein at least a portion of the precisely shaped asperities include a flange.

22. ) The polishing pad of claim 1, wherein the polishing layer includes a plurality of nanometer-size topographical features on at least one of the surface of the precisely shaped asperities, the surface of the precisely shaped pores and the surface of the land region.

23. ) The polishing pad of claim 22, wherein the plurality of nanometer sized features include regular or irregularly shaped grooves, wherein the width of the grooves is less than about 250 nm.

24. ) The polishing pad of claim 1, wherein the working surface comprises a secondary surface layer and a bulk layer and wherein the chemical composition in at least a portion of the secondary surface layer differs from the chemical composition within the bulk layer.

25. ) The polishing pad of claim 24, wherein the chemical composition in at least a portion of the secondary surface layer, which differs from the chemical composition within the bulk layer, includes silicon.

26. ) The polishing pad of claim 1, wherein at least one of the receding contact angle and advancing contact angle of the secondary surface layer is less than the corresponding receding contact angle and advancing contact angle of the bulk layer.

27. ) The polishing pad of claim 26, wherein at least one of the receding contact angle and advancing contact angle of the secondary surface layer is at least about 20°

less than the corresponding receding contact angle or advancing contact angle of the bulk layer.

28. ) The polishing pad of claim 1, wherein the receding contact angle of the working surface is less than about 50°

.

29. ) The polishing pad of claim 1, wherein the receding contact angle of the working surface is less than about 30°

.

30. ) The polishing pad of claim 1, wherein the polishing layer is substantially free of inorganic abrasive particles.

31. ) The polishing pad of claim 1, wherein the polishing layer further comprises a plurality of independent or inter-connected macro-channels.

32. ) The polishing pad of claim 1, further comprising a subpad, wherein the subpad is adjacent to the second surface of the polishing layer.

33. ) The polishing pad of claim 32, further comprising a foam layer, wherein the foam layer is interposed between the second surface of the polishing layer and the subpad.

34. ) A polishing system comprising the polishing pad of claim 1 and a polishing solution.

35. ) The polishing system of claim 34, wherein the polishing solution is a slurry.

36. ) The polishing system of claim 35, wherein the polishing layer contains less than 1% by volume inorganic abrasive particles.

37. ) The polishing pad of claim 1, further comprising at least one second polishing layer having a working surface and a second surface opposite the working surface;

wherein the working surface includes a plurality of precisely shaped pores, a plurality of precisely shaped asperities and a land region;

wherein each pore has a pore opening, each asperity has an asperity base, and a plurality of the asperity bases are substantially coplanar relative to at least one adjacent pore opening;

wherein the depth of the plurality of precisely shaped pores is less than the thickness of the land region adjacent to each precisely shaped pore and the thickness of the land region is less than about 5 mm;

wherein the at least one second polishing layer comprises a polymer; and

wherein the second surface of the polishing layer is adjacent to the working surface of the at least one second polishing layer.

38. ) The polishing pad of claim 37, further comprising an adhesive layer disposed between the second surface of the polishing layer and the working surface of the at least one second polishing layer.

39. ) The polishing pad of claim 38, wherein the adhesive layer is a pressure sensitive adhesive layer.

40. ) The polishing pad of claim 37, further comprising a foam layer disposed between the second surface of the polishing layer and the working surface of the at least one second polishing layer and a second foam layer adjacent the second surface of the at least one second polishing layer.

41. ) A method of polishing a substrate, the method comprising:

providing a polishing pad according to claim 1;

providing a substrate;

contacting the working surface of the polishing pad with the substrate surface;

moving the polishing pad and the substrate relative to one another while maintaining contact between the working surface of the polishing pad and the substrate surface;

and wherein polishing is conducted in the presence of a polishing solution.

42. ) The method of polishing a substrate of claim 41, wherein the substrate is a semiconductor wafer.

43. ) The method of polishing a substrate of claim 41, wherein the semiconductor wafer surface in contact with the working surface of the polishing pad includes at least one of a dielectric material and an electrically conductive material.