Polishing pad and method for manufacturing semiconductor device

• US 20060037699A1
• Filed: 11/27/2003
• Published: 02/23/2006
• Est. Priority Date: 11/27/2002
• 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: Shimomura, Tetsuo, Yamada, Takatoshi, Kazuno, Atsushi, Ogawa, Kazuyuki, Nakamori, Masahiko, Watanabe, Kimihiro
• Granted Patent: US 8,845,852 B2
• Time in Patent Office: Days
• US Class Current: 156/345.120
• CPC Class Codes: B24B 37/013 Devices or means for detecting lapping completion
• CPC Class Codes: B24B 37/205 provided with a window for inspecting the surface of the work being lapped

Abstract

A polishing pad enabling a highly precise optical endpoint sensing during the polishing process and thus having excellent polishing characteristics (such as surface uniformity and in-plane uniformity) is disclosed. A polishing pad enabling to obtain the polishing profile of a large area of a wafer is also disclosed. A polishing pad of a first invention comprises a light-transmitting region having a transmittance of not less than 50% over the wavelength range of 400 to 700 nm. A polishing pad of a second invention comprises a light-transmitting region having a thickness of 0.5 to 4 mm and a transmittance of not less than 80% over the wavelength range of 600 to 700 nm. A polishing pad of a third invention comprises a light-transmitting region arranged between the central portion and the peripheral portion of the polishing pad and having a length (D) in the diametrical direction which is three times or more longer than the length (L) in the circumferential direction.

Claims

1. A polishing pad used in chemical mechanical polishing and having a polishing region and a light-transmitting region, said polishing pad having at least one of the following characteristics:

i) light transmittance in the light-transmitting region throughout the wavelength range of 400 to 700 nm is 50% or more;

ii) a thickness of the light-transmitting region is 0.5 to 4 mm. and light transmittance in the light-transmitting region throughout the wavelength range of 600 to 700 nm is 80% or more;

or iii) the light-transmitting region is arranged between a central portion and a peripheral portion of the polishing pad, and a length (D) in a diametrical direction is 3 times or more longer than a length (L) in a circumferential direction.

2. The polishing pad according to claim 1, wherein a rate of change of the light transmittance in the light-transmitting region in wavelengths of 400 to 700 nm represented by the following equation is 50% or less:

the rate of change (%)={(maximum transmittance in 400 to 700 nm−

minimum transmittance in 400 to 700 nm)/maximum transmittance in 400 to 700 nm}×

100.

3. The polishing pad according to claim 1, wherein the light transmittance in the light-transmitting region at a wavelength of 400 nm is 50% or more, and the transmittance in the light-transmitting region throughout the wavelength range of 500 to 700 nm is 90% or more.

4. The polishing pad according to any one of claims 1, wherein a difference among respective light transmittances in the light-transmitting region in 500 to 700 nm is 5% or less.

7. The polishing pad according to claim 1, wherein a shape of the light-transmitting region is rectangular.

8. The polishing pad according to claim 1, wherein a length (D) in a diametrical direction is ¼

to ½

relative to a diameter of a material to be polished.

9. The polishing pad according to claims 1, wherein a scatter of the thickness of the light-transmitting region is 100 μ

m or less.

10. The polishing pad according to claims 1, wherein materials for forming the polishing region and the light-transmitting region are polyurethane resin.

11. The polishing pad according to claim 10, wherein the polyurethane resin as the material for forming the polishing region and the polyurethane resin as the material for forming the light-transmitting region comprise the same kinds of organic isocyanate, polyol and chain extender.

12. The polishing pad according to of claims 1, wherein a material for forming the light-transmitting region is non-foam.

13. The polishing pad according to claim 1, which does not have an uneven structure for retaining and renewing an abrasive liquid on a surface of the light-transmitting region on a polishing side.

14. The polishing pad according to claims 1, wherein a material for forming the polishing region is fine-cell foam.

15. The polishing pad according to of claims 1, wherein a surface of the polishing region on a polishing side is provided with grooves.

16. The polishing pad according to claim 14, wherein an average cell diameter of the fine-cell foam is 70 μ

m or less.

17. The polishing pad according to claims 1, wherein a specific gravity of the fine-cell foam is 0.5 to 1.0 g/cm³.

18. The polishing pad according to claims 1, wherein a hardness of the fine-cell foam is 45 to 65°

in terms of Asker D hardness.

19. The polishing pad according to claim 1, wherein a compressibility of the fine-cell foam is 0.5 to 5.0%.

20. The polishing pad according to claims 1, wherein a compression recovery of the fine-cell foam is 50 to 100%.

21. The polishing pad according to claims 1, wherein a storage elastic modulus of the fine-cell foam at 40°

C. at 1 Hz is 200 MPa or more.

22. A method of producing a semiconductor device, which comprises a step of polishing a surface of a semiconductor wafer with the polishing pad recited in claims 1.

5-6. -6. (canceled)