Polishing pad composition and method of use

• US 6,764,574 B1
• Filed: 08/22/2001
• Issued: 07/20/2004
• Est. Priority Date: 03/06/2001
• Status: Expired due to Fees

• Current Assignee: Exigent USA Incorporated
• Original Assignee: Psiloquest Incorporated
• Inventors: Richardson, Kathleen C., Obeng, Yaw S., Yokley, Edward M.
• Primary Examiner(s): ALANKO, ANITA KAREN
• Application Number:
  US09/938,150
• Time in Patent Office: 1,063 Days
• Field of Search: 156/345.12, 451/287-290, 451/526, 451/921, 383/42, 383/63, 383/64, 383/113, 206/204, 206/205, 206/207
• US Class Current: 156/345.12
• CPC Class Codes: B24B 37/24 characterised by the composition or properties of the pad materials
• CPC Class Codes: B24D 3/28 Resins or natural or synthetic macromolecular compounds B24D3/22 takes precedence
• CPC Class Codes: B24D 3/346 utilised during polishing, or grinding operation

Abstract

The present invention is directed, in general, to packaged polishing pads for chemical mechanical polishing of semiconductor wafers and integrated circuits. More specifically, the invention is directed to a method of preparing and packing the pad and the packaging therefor. Prior to placing the pad on a platen and polishing with the pad, a polishing pad having an hygroscopic absorbency is soaked with an aqueous media for a time sufficient to equilibrate the pad. The pad maybe packaged by placement in a sealable moisture tight package after soaking or before soaking along with a sufficient quantity of aqueous media to allow the pad to equilibrate.

Claims

1. A packaged polishing pad, comprising:

a sealable moisture tight package having a dimension sufficient to contain a polishing pad therein; and

a polishing pad soaked in an aqueous medium comprising an additive configured to simulate a CMP slurry and located within the sealable moisture tight package, wherein said polishing pad is configured for use in chemical mechanical polishing of a semiconductor wafer in conjunction with a polishing slurry.

2. The packaged polishing pad as recited in claim 1 wherein the aqueous media is at about 10 C. to 45 C. and ambient pressure.

3. The packaged polishing pad as recited in claim 1 wherein the polishing pad is equilibrated with the aqueous media to at least about 10% to about 50% of the pad'"'"'s maximum absorbency.

4. The packaged polishing pad as recited in claim 1 wherein the pad comprises a polymer selected from the group consisting of:

6.6 nylon;

6.12 nylon;

polyketone; and

polyurethane.

5. The packaged polishing pad as recited in claim 1 wherein the additive comprises a buffer.

6. The packaged polishing pad as recited in claim 5 wherein the buffer is an acidic buffer having a pH ranging from about 2.0 to about 7.0.

7. The packaged polishing pad as recited in claim 5 wherein the buffer is a basic buffer having a pH ranging from about 7.0 to about 14.0.

8. The packaged polishing pad as recited in claim 1 wherein the additive is selected from the group consisting of an oxidant, an abrasive, and an organic amine.

9. The packaged polishing pad as recited in claim 8 wherein the organic amine is ethanol amine.

10. The packaged polishing pad as recited in claim 8 wherein the additive comprises an abrasive and the abrasive is selected from the group consisting of alumina and silica.

11. The packaged polishing pad as recited in claim 1 wherein the sealable moisture tight package is comprised of a flexible plastic material.

12. The packaged polishing pad as recited in claim 11 wherein the flexible plastic material is a heat sealable material.

13. The packaged polishing pad as recited in claim 11 wherein the flexible plastic material is mechanically sealable.

14. The packaged polishing pad as recited in claim 1 wherein the polishing slurry further includes an abrasive.