Process for removing contaminant from a surface and composition useful therefor
View Patent ↗Particulate and metal ion contamination is removed from a surface, such as a semiconductor wafer containing copper damascene or dual damascene features, employing a fluoride-free aqueous composition comprising a dicarboxylic acid and/or salt thereof; and a hydroxycarboxylic acid and/or salt thereof or amine group containing acid.
1. A fluoride-free aqueous composition for removing particulate contaminants from a copper surface after CMP planarization without adversely affecting the copper surface which consists essentially of about 0.003 to about 8% by weight of malonic acid;
about 0.003 to about 8% by weight of oxalic acid;
about 0.003 to about 4% by weight of citric acid; and the remainder being substantially water; and
having a pH of about 1 to about 4.
2. The composition of claim 1 comprising about 0.2% by weight of citric acid; about 0.1% by weight of malonic acid and about 0.2% by weight of oxalic acid.
3. The composition of claim 1 which further comprises a biocide.
4. The composition of claim 3 wherein the amount of said biocide is up to about 0.002% by weight.
5. The composition of claim 3 wherein the amount of said biocide is about 0.00005% by weight.
6. The composition of claim 1 wherein the pH is up to about 2.
7. A fluoride-free aqueous composition for removing particulate contaminants from a copper surface after CMP planarization without adversely affecting the copper surface which consists essentially of about 0.005 to about 16% by weight of at least one dicarboxylic acid, salt thereof or mixture thereof;
about 0.003 to about 4% by weight of glycine; and the remainder being substantially water; and
having a pH of about 1 to about 3.
8. The composition of claim 7 wherein the dicarboxylic acid or salt thereof has two to six carbon atoms.
9. The composition of claim 7 wherein the dicarboxylic acid is selected from the group consisting of oxalic acid, malonic acid, succinic acid, glutaric acid, adipic acid, maleic acid and fumaric acid.
10. A fluoride-free aqueous composition for removing particulate contaminants from a copper surface after CMP planarization without adversely affecting the copper surface which consists essentially of about 0.005 to about 16% by weight of at least one dicarboxylic acid, salt thereof or mixture thereof;
about 0.003 to about 4% by weight of at least one amine group containing acid, salt thereof or mixture thereof; and the remainder being substantially water; and
having a pH of about 1 to about 3; and wherein the dicarboxylic acid comprises a mixture of malonic acid and oxalic acid.
11. The composition of claim 10 wherein said at least one amine group containing acid is glycine.
12. A fluoride-free aqueous composition for removing particulate contaminants from a copper surface after CMP planarization without adversely affecting the copper surface which consists essentially of about 0.003 to about 8% by weight of malonic acid;
about 0.003 to about 8% by weight of oxalic acid;
about 0.003 to about 4% by weight of glycine; and the remainder being substantially water; and
having a pH of about 1 to about 4.
13. The composition of claim 12 comprising about 0.25% by weight of glycine; about 0.1% by weight of malonic acid and about 5% by weight of oxalic acid.
14. The composition of claim 12 which further comprises a biocide.
15. The composition of claim 14 wherein the amount of said biocide is up to about 0.002% by weight.
16. The composition of claim 14 wherein the amount of said biocide is about 0.00005% by weight.
17. The composition of claim 12 wherein the pH is up to about 2.