Process for removing contaminant from a surface and composition useful therefor description
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 fluo-ride-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 consisting of
about 0.005 to about 16% by weight of at least two dicarboxylic acids, salt thereof or mixture thereof;
about 0.003 to about 4% by weight of at least one hydroxyl carboxylic acid; and the remainder being substantially water; and
having a pH of about 1 to about 4.
2. The composition of claim 1 wherein the dicarboxylic acid has two to six carbon atoms.
3. The composition of claim 1 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.
4. The composition of claim 1 wherein the dicarboxylic acid comprises a mixture of malonic acid and oxalic acid.
5. The composition of claim 4 wherein the amount of said malonic acid is about 0.003 to about 8% by weight and the amount of said oxalic acid is about 0.003 to about 8% by weight.
6. The composition of claim 1 wherein the hydroxyl carboxylic acid is selected from the group consisting of malic acid, tartaric acid and citric acid.
7. The composition of claim 1 wherein the hydroxyl carboxylic acid is citric acid.