Method and apparatus for processing wafer-shaped articles
In a method and apparatus for treating a surface of an article, an improved rinse liquid prevents build-up of static charge while avoiding damages to certain types of exposed metal-containing surfaces. In one embodiment, a semiconductor wafer having structures including at least one of cobalt, nickel and platinum is rotated on a spin chuck, as a rinse liquid is dispensed onto a surface of the wafer. The rinse liquid is a dilute aqueous solution of a base of the formula in which R 1 , R 2 and R 3 are each independently selected from hydrogen and C 1-4 alkyl. The base has a boiling point less than 100° C., and the rinse liquid has a pH in the range of 8 to 10.
1. A method for treating a surface of an article, comprising:
rotating an article on a spin chuck about a rotation axis, wherein the article comprises a surface generally perpendicular to said rotation axis that comprises structures including a material that comprises at least one metal selected from the group consisting of cobalt, nickel, copper and platinum;
dispensing a rinse liquid onto said surface, said rinse liquid consisting essentially of an aqueous solution of a base of the formula
in which R 1 , R 2 and R 3 are each independently selected from hydrogen and C 1-4 alkyl, said base having a boiling point less than 100° C., said rinse liquid having a pH in the range of 8 to 10.
2. The method according to claim 1 , wherein the article is a semiconductor wafer.
3. The method according to claim 1 , wherein said material is a silicide.
4. The method according to claim 1 , wherein said base is a gas at 25° C. and 101.325 kPa.
5. The method according to claim 4 , wherein said base is NH 3 .
6. The method according to claim 5 , wherein said NH 3 is present in said rinse liquid at a concentration from 10 −5 mol/L to 10 −4 mol/L.
7. The method according to claim 1 , wherein said material is a cobalt silicide layer formed on at least one terminal of transistors formed on said surface.
8. The method according to claim 1 , wherein said article is rotated at a speed of 10-2000 rpm.
9. The method according to claim 1 , wherein said surface faces away from said spin chuck.
10. The method according to claim 1 , further comprising continuing to rotate said article on said spin chuck after ceasing dispensing said rinse fluid.