Claims
- 1. In an aqueous polishing composition of a pH, said composition having abrasive particles of a metal oxide providing ions upon dissolution, the improvement comprising: a soluble salt providing an equilibrium concentration of said ions at the pH, which avoids drift of the pH caused by dissolution of the particles.
- 2. In the aqueous polishing composition as recited in claim 1, wherein said ions are metal ions.
- 3. In the aqueous polishing composition as recited in claim 1, wherein the pH is greater than 5, and said ions are metal ions.
- 4. In the aqueous polishing composition as recited in claim 1, wherein the particles are alumina, and said ions are ions of an aluminum oxide.
- 5. In the aqueous polishing composition as recited in claim 1, wherein the pH is less than 5, and said ions are metal ions.
- 6. In the aqueous polishing composition as recited in claim 1, wherein the particles are alumina, and said ions are metal ions of aluminum.
- 7. In the aqueous polishing composition as recited in claim 1, wherein the particles are alumina, and the soluble salt is aluminum salt.
- 8. In the aqueous polishing composition as recited in claim 1, wherein the particles are alumina, and the soluble salt is an aluminum salt when the pH is about 1.5 to 5.
- 9. In a method of chemical mechanical polishing wherein, an interface of a polishing pad and a substrate being polished by the polishing pad receives an aqueous polishing composition having particles of a metal oxide providing ions upon dissolution, the improvement comprising the step of: providing an equilibrium concentration of said ions at a pH of the aqueous polishing composition, which avoids drift of the pH caused by dissolution of the particles.
- 10. In the method as recited in claim 9, wherein said ions are metal ions and the pH is greater than 5.
- 11. In the method as recited in claim 9, wherein said ions are metal ions and the pH is greater than 5, and the particles comprise alumina.
- 12. In the method as recited in claim 9, wherein said ions are metal ions and the pH is less than 5.
- 13. In the method as recited in claim 9, wherein said ions are metal ions and the pH is less than 5, and the particles comprise alumina.
- 14. In the method as recited in claim 9, wherein the aqueous polishing composition with a soluble salt provides said equilibrium concentration of said ions at the pH.
Parent Case Info
This utility application claims the benefit of U.S. Provisional Patent Application No. 60/170,612 filed on Dec. 14, 1999.
US Referenced Citations (6)
Non-Patent Literature Citations (1)
Entry |
Kaufman et al.; “Chemical-Mechanical Polishing for Fabricating Patterned W Metal Features as Chip Interconnects”; Journal of the Electrochemical Society; Nov., 1991; pp. 3460-3464; vol. 138. No. 11; The Electrochemical Society, Inc. |
Provisional Applications (1)
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Number |
Date |
Country |
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60/170612 |
Dec 1999 |
US |