Polishing pad

• US 7,871,309 B2
• Filed: 12/08/2005
• Issued: 01/18/2011
• Est. Priority Date: 12/10/2004
• Status: Active Grant

• Current Assignee: ROHM and HAAS Electronic Materials CMP Holdings Incorporated (DuPont de Nemours, Inc.)
• Original Assignee: TOYO Tire & Rubber Company Limited (Toyo Tire Corporation)
• Inventors: Yamada, Takatoshi, Watanabe, Masahiro, Ogawa, Kazuyuki, Nakamori, Masahiko, Shimomura, Tetsuo, Kazuno, Atsushi, Nakai, Yoshiyuki
• Primary Examiner(s): Eley; Timothy V
• Application Number:
  US11/720,964
• Publication Number:
  US 20090253353A1
• Time in Patent Office: 1,867 Days
• Field of Search: 512/93, 512/97, 512/98, 451/6, 451/287, 451/288, 451/290, 451/527, 451/533, 451/534, 451/41, 451/59, 451/63
• US Class Current: 451/41
• CPC Class Codes: B24B 37/205 provided with a window for inspecting the surface of the work being lapped
• CPC Class Codes: Y10T 428/24339 Keyed
• CPC Class Codes: Y10T 428/24992 Density or compression of components

Abstract

It is an object of the invention to provide a polishing pad capable of high precision optical detection of an endpoint during polishing in progress and prevention of slurry leakage from between a polishing region and a light-transmitting region during the use thereof even after the polishing pad has been used for a long period. It is a second object of the invention to provide a polishing pad capable of suppression of deterioration of polishing characteristics (such as in-plane uniformity) and generation of scratches due to a difference in behavior of a polishing region and a light-transmitting region during polishing. It is a third object of the invention to provide a polishing pad having a polishing region and a light-transmitting region with a concentration of a specific metal equal to or lower than a specific value (threshold value).

Claims

1. A polishing pad having a polishing region and a light-transmitting region, wherein a water permeation preventive layer is provided on one surface of the polishing region and the light-transmitting region, and the light-transmitting region and the water permeation preventive layer are made of the same material integrally in a single piece,

wherein each of the polishing region and the light-transmitting region comprise a polymer made from raw materials on equipment that comprises surfaces contacting said raw materials, wherein said surfaces comprise no metal other than chrome such that each of said regions have a concentration of Fe of 0.3 ppm or less, a concentration of Ni of 1.0 ppm or less, a concentration of copper of 0.5 ppm or less, a concentration of zinc of 0.1 ppm or less and a concentration of Al of 1.2 ppm or less.

2. The polishing pad according to claim 1, wherein no interface exists between the light-transmitting region and the water permeation preventive layer.

3. The polishing pad according to claim 1, wherein the water permeation preventive layer has a cushioning property.

4. The polishing pad according to claim 1, wherein a material of which the light-transmitting region and the water permeation preventive layer are made is a non-foam.

5. The polishing pad according to claim 1, wherein a material of which the polishing region is made is a fine foam.

6. The polishing pad according to claim 1, wherein the light-transmitting region has no depression and protrusion structure for holding or renewing a polishing liquid on a polishing side surface thereof.

7. The polishing pad according to claim 1, wherein the polishing region has a depression and protrusion structure for holding or renewing a polishing liquid on a polishing side surface thereof.

8. A method for manufacturing the polishing pad according to claim 1, comprising:

a step of forming an aperture for providing the light-transmitting region in the polishing region;

a step of casting a material into a mold having shapes of the light-transmitting region and the water permeation preventive layer and curing the material to thereby form a transparent member into which the light-transmitting region and the water permeation preventive layer are made integrally as a single piece; and

a step of fittingly inserting the light-transmitting region into the aperture in the polishing region to thereby laminate the polishing region and the transparent member.

9. A method for manufacturing the polishing pad according to claim 1, comprising:

a step of forming an aperture for providing the light-transmitting region in the polishing region; and

a step of casting a material into a space section having shapes of the aperture and the water permeation preventive layer and curing the material to thereby form a transparent member into which the light-transmitting region and the water permeation preventive layer are made integrally as a single piece.

10. A method for manufacturing a semiconductor device comprising steps of polishing a surface of a semiconductor wafer using a polishing pad according to claim 1.

11. A polishing pad having a polishing region and a light-transmitting region according to claim 1, wherein a compressibility of the light-transmitting region is more than a compressibility of the polishing region.

12. The polishing pad according to claim 11, wherein a compressibility of the light-transmitting region is in the range of from 1.5 to 10%.

13. The polishing pad according to claim 11, wherein a compressibility of the polishing region is in the range of from 0.5 to 5%.

14. The polishing pad according to claim 11, wherein the light-transmitting region has a light transmittance of 80% or more at a wavelength in all the region of from 500 to 700 nm in wavelength.

15. A method for manufacturing a semiconductor device comprising steps of polishing a surface of a semiconductor wafer using a polishing pad according to claim 11.

16. A polishing pad, in which a polishing layer having a polishing region and an aperture A for providing a light-transmitting region therein and a cushion layer having an aperture B smaller than the light-transmitting region are laminated one on the other so that the apertures A and B are superimposed one on the other, the light-transmitting region is provided on the aperture B and in the aperture A and a water non-permeable elastic member having a hardness lower than the polishing region and the light-transmitting region is provided in an annular groove existing between the aperture A and the light-transmitting region,

wherein the water non-permeable elastic member is made of a water non-permeable resin composition containing a water non-permeable resin of at least one kind selected from the group consisting of a rubber, a thermoplastic elastomer and a reaction curable resin, and

wherein the water non-permeable elastic member is lower in height than the annular groove.

17. The polishing pad according to claim 16, wherein the water non-permeable elastic member has an Asker hardness A of 80 degrees or less.

18. A method for manufacturing the polishing pad according to claim 16, comprising:

a step of laminating a cushion layer on a polishing layer having a polishing region and an aperture A for providing the light-transmitting region;

a step of removing part of the cushion layer in the aperture A to form an aperture B smaller than the light-transmitting region in the cushion layer;

a step of providing the light-transmitting region on the aperture B and in the aperture A; and

a step of casting a water non-permeable resin composition into an annular groove existing between the aperture A and the light-transmitting region and curing the composition to thereby form a water non-permeable elastic member.

19. A method for manufacturing the polishing pad according to claim 16, comprising:

a step of laminating a polishing layer having a polishing region and an aperture A for providing the light-transmitting region and a cushion layer having an aperture B smaller than the light-transmitting region one on the other so that the apertures A and B are superimposed one on the other;

a step of providing the light-transmitting region on the aperture B and in the aperture A; and

a step of casting a water non-permeable resin composition into an annular groove existing between the aperture A and the light-transmitting region and curing the composition to thereby form a water non-permeable elastic member.

20. A method for manufacturing a semiconductor device comprising steps of polishing a surface of a semiconductor wafer using a polishing pad according to claim 16.

21. A polishing pad in which a polishing layer having a polishing region and a light-transmitting region and a cushion layer having an aperture B smaller than the light-transmitting region are laminated one on the other so that the light-transmitting region and the aperture B are superimposed one on the other and an annular water non-permeable elastic member is provided over a contact portion between the rear surface of the light-transmitting region and a section of the aperture B so as to cover the contact portion,

wherein the water non-permeable elastic member is made of a water non-permeable resin composition containing a water non-permeable resin of at least one kind selected from the group consisting of a rubber, a thermoplastic elastomer and a reaction curable resin.

22. The polishing pad according to claim 21, wherein the water non-permeable elastic member has an Asker hardness A of 80 degrees or less.

23. A method for manufacturing the polishing pad according to claim 21, comprising:

a step of laminating a polishing layer having a polishing region and a light-transmitting region and a cushion layer having an aperture B smaller than the light-transmitting region one on the other so that the light-transmitting region and the aperture B are superimposed one on the other; and

a step of coating a water non-permeable resin composition over a contact portion between the rear surface of the light-transmitting region and a section of the aperture B to cure the wet coat and to thereby form an annular water non-permeable elastic member so as to cover the contact portion.

24. A method for manufacturing the polishing pad according to claim 21, comprising:

a step of laminating a cushion layer on a polishing layer having a polishing region and an aperture A for providing the light-transmitting region so as to be inserted therein;

a step of removing part of the cushion layer in the aperture A to form an aperture B smaller than the light-transmitting region in the cushion layer;

a step of providing the light-transmitting region on the aperture B and in the aperture A; and

a step of coating a water non-permeable resin composition over a contact portion between the rear surface of the light-transmitting region and a section of the aperture B to cure the wet coat and to thereby form an annular water non-permeable elastic member so as to cover the contact portion.

25. A method for manufacturing the polishing pad according to claim 21, comprising:

a step of laminating a polishing layer having a polishing region and an aperture A for providing the light-transmitting region so as to be inserted therein and a cushion layer having the aperture B smaller than the light-transmitting region one on the other so that the apertures A and B are superimposed one on the other;

a step of providing the light-transmitting region on the aperture B and in the aperture A; and

a step of coating a water non-permeable resin composition over a contact portion between the rear surface of the light-transmitting region and a section of the aperture B to cure the wet coat and to thereby form an annular water non-permeable elastic member so as to cover the contact portion.

26. A method for manufacturing a semiconductor device comprising steps of polishing a surface of a semiconductor wafer using a polishing pad according to claim 21.

27. A polishing pad having a polishing region and a light-transmitting region, wherein each of the polishing region and the light-transmitting region comprise a polymer made from raw materials on equipment that comprises surfaces contacting said raw materials, wherein said surfaces comprise no metal other than chrome such that each of said regions have a concentration of Fe of 0.3 ppm or less, a concentration of Ni of 1.0 ppm or less, a concentration of copper of 0.5 ppm or less, a concentration of zinc of 0.1 ppm or less and a concentration of Al of 1.2 ppm or less.

28. The polishing pad according to claim 27, wherein a material of the polishing region and the light-transmitting region is a polymer of at least one kind selected from the group consisting of a polyolefin resin, a polyurethane resin, a (meth)acrylic resin, a silicone resin, a fluororesin, a polyester resin, a polyamide resin, a polyamideimide resin and a photosensitive resin.

29. A method for manufacturing a semiconductor device comprising steps of polishing a surface of a semiconductor wafer using a polishing pad according to claim 27.