Methods for making reinforced wafer polishing pads utilizing direct casting and apparatuses implementing the same

• US 6,572,463 B1
• Filed: 12/27/2000
• Issued: 06/03/2003
• Est. Priority Date: 12/27/2000
• Status: Expired due to Fees

• Current Assignee: Applied Materials Incorporated
• Original Assignee: Lam Research Corporation
• Inventors: Zhao, Eugene Y., Dai, Fen, Xu, Cangshan
• Primary Examiner(s): Hail, III, Joseph J.
• Assistant Examiner(s): Thomas, David B.
• Application Number:
  US09/752,703
• Time in Patent Office: 888 Days
• Field of Search: 451/41, 451/59, 451/167, 451/168, 451/172, 451/173, 451/207, 451/296, 451/300, 451/336, 451/489, 451/526, 451/533, 451/534, 451/536-539
• US Class Current: 451/526
• CPC Class Codes: B24B 37/26 characterised by the shape of the lapping pad surface, e.g. grooved
• CPC Class Codes: B24D 11/00 Constructional features of flexible abrasive materials; Special features in the manufacture of such materials
• CPC Class Codes: B24D 18/0009 using moulds or presses

Abstract

A seamless polishing apparatus for utilization in chemical mechanical polishing is disclosed. The seamless polishing apparatus includes a base belt that has a reinforcement layer and a cushioning layer. The seamless polishing apparatus also includes a polishing pad that is attached to the base belt as a result of a direct casting of a polymeric precursor on a top surface of the cushioning layer. In addition, the cushioning layer is an intermediary layer between the polishing belt pad and the base belt.

Claims

1. A seamless polishing apparatus for utilization in chemical mechanical polishing, comprising:

a base belt, the base belt including a reinforcement layer and a cushioning layer; and

a polishing pad, the polishing pad being attached to the base belt as a result of a direct casting of a polymeric precursor on a top surface of the cushioning layer;

wherein the cushioning layer is an intermediary layer between the polishing belt pad and the base belt.

2. A seamless polishing apparatus for utilization in chemical mechanical polishing as recited in claim 1, further comprising:

a protective liner attached to a bottom surface of the base belt.

3. A seamless polishing apparatus for utilization in chemical mechanical polishing as recited in claim 2 wherein the protective liner is polyethylene.

4. A seamless polishing apparatus for utilization in chemical mechanical polishing as recited in claim 2 wherein the protective liner is between about 5 mils and about 40 mils in thickness.

5. A seamless polishing apparatus for utilization in chemical mechanical polishing as recited in claim 2 wherein the protective liner is about 20 mils in thickness.

6. A seamless polishing apparatus for utilization in chemical mechanical polishing as recited in claim 1, wherein, the polymeric precursor is at least one of a semi-solid form, a liquefied form, and a gel form.

7. A seamless polishing apparatus for utilization in chemical mechanical polishing as recited in claim 1, wherein the polymeric precursor is a liquid polyurethane.

8. A seamless polishing apparatus for utilization in chemical mechanical polishing as recited in claim 1, wherein the reinforcement layer is one of stainless steel and a Kevlar-type material and is between about 5 mils and 50 mils in thickness.

9. A seamless polishing apparatus for utilization in chemical mechanical polishing as recited in claim 1, wherein the polishing pad is polyurethane, and the polishing pad is between about 30 mils and 100 mils in thickness.

10. A seamless polishing apparatus for utilization in chemical mechanical polishing as recited in claim 1, wherein the cushioning layer is made up of open-celled polyurethane and is between about 10 mils and about 100 mils.

12. A seamless polishing apparatus for utilization in chemical mechanical polishing as recited in claim 8, wherein the protective liner is polyethylene, and the polyethylene is between about 5 mils and about 40 mils in thickness.

13. A seamless polishing apparatus for utilization in chemical mechanical polishing as recited in claim 8, wherein the liquid polymer is a liquid polyurethane.

11. A seamless polishing apparatus for utilization in chemical mechanical polishing, comprising:

a polishing pad, the polishing pad being shaped like a belt and configured to have no seams;

a base belt, the base belt including a reinforcement layer and a cushioning layer, the reinforcement layer being made of one of stainless steel and a Kevlar-type material;

a protective liner attached to a bottom surface of the base belt;

wherein the cushioning layer is an intermediary layer between the polishing belt pad and the base belt, and the polishing pad is attached to the base belt as a result of direct casting of a liquid polymer onto a top surface of the cushioning layer.

14. A seamless polishing apparatus for utilization in chemical mechanical polishing, comprising:

a polishing pad, the polishing pad being shaped like a belt and is a contiguous unit;

a base belt, the base belt including a reinforcement layer and a cushioning layer, the reinforcement layer being made of one of stainless steel and a Kevlar-type material;

a protective liner attached to a bottom surface of the base belt, the protective film being a polyethylene film;

wherein the cushioning layer is an intermediary layer between the polishing belt pad and the base belt, and the polishing pad is attached to the base belt as a result of direct casting of a polymeric precursor onto a top surface of the cushioning layer.

15. A seamless polishing apparatus for utilization in chemical mechanical polishing as recited in claim 14, wherein the polymeric precursor is at least one of a liquid form, a semi-solid form, and a gel form.

16. A seamless polishing apparatus for utilization in chemical mechanical polishing as recited in claim 14, wherein the polymeric precursor is a liquid polyurethane.

17. A seamless polishing apparatus for utilization in chemical mechanical polishing as recited in claim 14, wherein the polyethylene film is about 20 mils in thickness.

18. A seamless polishing apparatus for utilization in chemical mechanical polishing, comprising:

a polishing pad, the polishing pad being shaped like a belt and configured to have no seams, the polishing pad being generated as a result of a solidification of a polymeric precursor from a direct casting, and the polishing pad being bet ween about 30 mils and about 100 mils in thickness and having a grooved top surface;

a base belt, the base belt including a reinforcement layer and a cushioning layer, the cushioning layer being between about 10 mils and about 100 mils in thickness, and the reinforcement layer being between about 5 mils and about 50 mils in thickness;

a protective liner attached to a bottom surface of the base belt, the protective liner being polyethylene; and

wherein the cushioning layer is an intermediary layer between the polishing belt pad and the base belt, the direct casting is an application of a liquid polymer to a top surface of the cushioning layer, and the polishing pad is attached to the base belt as a result of the direct casting without use of an adhesive, and the liquid polymer enters pores of the cushioning layer during the direct casting to create a greater contact surface with the cushioning layer thereby increasing attachment between the resulting polishing pad from a solidified liquid polymer and the cushioning layer.

19. A method for generating a polishing pad structure for utilization in chemical mechanical polishing, comprising:

providing a reinforcement layer;

applying an adhesive film over the reinforcement layer;

attaching a cushioning layer on the adhesive film;

applying a polymeric precursor to the cushioning layer; and

curing the polishing pad structure;

wherein the polymeric precursor solidifies to form a polishing pad directly fused to the cushioning layer.

20. A method for generating a polishing pad structure for utilization in chemical mechanical polishing as recited in claim 19, wherein the adhesive film is a rubber-based adhesive.

21. A method for generating a polishing pad structure for utilization in chemical mechanical polishing as recited in claim 19, wherein the polymeric precursor is at least one of a liquid form, a semi-sold form, a gel form.

22. A method for generating a polishing pad structure for utilization in chemical mechanical polishing as recited in claim 19, wherein the polymeric precursor is a liquid polyurethane.

23. A method for generating a polishing pad structure for utilization in chemical mechanical polishing as recited in claim 19, wherein the polymeric precursor is applied to a top surface of the cushioning layer during a direct casting.

24. A method for generating a polishing pad structure for utilization in chemical mechanical polishing as recited in claim 19, wherein the polishing pad is attached to the base belt as a result of the direct casting without use of an adhesive, and the liquid polymer enters pores of the cushioning layer during the direct casting to create a greater contact surface with the cushioning layer thereby increasing attachment between the resulting polishing pad from the solidified liquid polymer and the cushioning layer.

25. A method for generating a polishing pad structure for utilization in chemical mechanical polishing, comprising:

providing a reinforcement layer;

applying an adhesive film over the reinforcement layer;

attaching a cushioning layer on the adhesive film;

applying a liquid polymeric precursor to the cushioning layer; and

curing the polishing pad structure for between about 12 hours to about 48 hours at a temperature between about 150 F to 300 F;

wherein the polymeric precursor solidifies to form a polishing pad directly fused to the cushioning layer, and the polishing pad is attached to the base belt as a result of the direct casting without use of an adhesive, and the liquid polymer enters pores of the cushioning layer during the direct casting to create a greater contact surface with the cushioning layer thereby increasing attachment between the resulting polishing pad from a solidified liquid polymer and the cushioning layer.

26. A method for generating a polishing pad structure for utilization in chemical mechanical polishing as recited in claim 25, wherein the adhesive film flows during the curing thereby increasing the surface area of adhesion.

27. A method for generating a polishing pad structure for utilization in chemical mechanical polishing, comprising:

providing a reinforcement layer, the reinforcement layer being one of stainless steel and a Kevlar-type material;

applying an adhesive film over the reinforcement layer, the adhesive film being a permanent rubber based adhesive;

attaching a cushioning layer on the adhesive film, the cushioning layer being made up of an open-celled polyurethane material;

applying a liquid polymeric precursor to the cushioning layer, the liquid polymeric precursor being a liquid polyurethane, the liquid polyurethane forming a seamless polyurethane layer; and

curing the polishing pad structure for about 18 hours at a temperature of about 212 F;

wherein the adhesive film flows during the curing thereby increasing the surface area of adhesion.