Post plasma ashing wafer cleaning formulation
View Patent ↗A semiconductor wafer cleaning formulation for use in post plasma ashing semiconductor fabrication comprising at least one organic chelating agent and at least one polar solvent, wherein the chelating agent and polar solvent are in sufficient amounts to effectively remove inorganic compound residue from a semiconductor wafer. Preferably, the chelating agent is selected from the group consisting of 2,4-Pentanedione, Malonic acid, Oxalic acid, p-Toluenesulfonic acid, and Trifluoroacetic acid; and the polar solvent is selected from the group consisting of Water, Ethylene glycol, N-Methylpyrrolidone (NMP), Gamma butyrolactone (BLO), Cyclohexylpyrrolidone (CHP), Sulfolane, 1,4-Butanediol, and Butyl carbitol.
1. A semiconductor wafer cleaning formulation for use in post plasma ashing semiconductor fabrication comprising at least one organic chelating agent and at least two polar solvents, wherein the chelating agent and polar solvents are in sufficient amounts to effectively remove residue from a semiconductor wafer, wherein said formulation is free from components selected from the group consisting of strong inorganic acids, strong bases, amine-containing components, and catalysts, and wherein the at least two polar solvents comprise water and at least one organic solvent selected from the group consisting of: Cyclohexylpyrrolidone (CHP) and 1,4-Butanediol.
2. The cleaning formulation according to claim 1 wherein the amounts of the organic chelating agent and said at least two polar solvents range from about 2% to about 98%.
3. The cleaning formulation according to claim 1 wherein the at least one organic chelating agent includes a first chelating agent in a percentage by weight range, wherein the first chelating agent and its percentage by weight range are selected from the group consisting of: 2,4-Pentanedione 0.01-98%, Malonic acid 0.01-10%, Oxalic acid 0.01-5%, p-Toluenesulfonic acid 0.01-10%, and Trifluoroacetic acid 0.01-12%.
4. The cleaning formulation according to claim 2 wherein the amount of water in percent by weight, based on the total weight of the formulation, is from 0.01% to 98%.
5. The cleaning formulation according to claim 3 wherein the amount of the at least one organic solvent in percent by weight, based on the total weight of the formulation, is selected from the group consisting of Cyclohexylpyrrolidone (CHP) 0.01-75% and 1,4-Butanediol 0.01-75%.
6. The cleaning formulation according to claim 1 wherein sulfonic acid is not present in said formulation.
7. The cleaning formulation according to claim 1 wherein the residue is inorganic.
8. A semiconductor wafer cleaning formulation for use in post plasma ashing semiconductor fabrication, wherein said formulation is free from components selected from the group consisting of strong inorganic acids, strong bases, amine-containing components, and catalysts, wherein said formulation is selected from the group consisting of:
a. Malonic acid from about 5% to about 10%;
CHP from about 20% to about 75%; and
Water from about 20% to about 40% and
b. Malonic acid from about 5% to about 10%;
1,4-Butanediol from about 20% to about 75%; and
Water from about 20% to about 40%.
9. A method for fabricating a semiconductor wafer which includes the steps comprising:
cleaning said wafer using a chemical formulation comprising at least one organic chelating agent and at least two polar solvents wherein the organic chelating agent and polar solvents are in sufficient amounts to effectively remove residues from a semiconductor wafer, wherein said chemical formulation is free from components selected from the group consisting of strong inorganic acids, strong bases, amine-containing components, and catalysts, and wherein the at least two polar solvents comprise water and at least one organic solvent selected from the group consisting of: Cyclohexylpyrrolidone (CHP) and 1,4-Butanediol.
10. The method according to claim 9 wherein the amounts of chelating agent and said at least two polar solvents range from about 2% to about 9%.
11. The method according to claim 9 wherein the organic chelating agent in the percentage by weight range shown is selected from the group consisting of: 2,4-Pentanedione 0.01-98%, Malonic acid 0.01-10%, Oxalic acid 0.01-5%, p-Toluenesulfonic acid 0.01-10%, and Trifluoroacetic acid 0.01-12%.
12. The method according to claim 10 wherein the amount of water in percent by weight, based on the total weight of the formulation, is from 0.01% to 98%.
13. The method according to claim 11 wherein the amount of the at least one organic solvent in percent by weight, based on the total weight of the formulation, is selected from the group consisting of: Cyclohexylpyrrolidone (CHP) 0.01-75% and 1,4-Butanediol 0.01-75%.
14. The method according to claim 13 wherein the wafer is exposed to said chemical formulation for a time period of 15-60 minutes at a temperature range of 45-75° C.
15. The method according to claim 9 wherein sulfonic acid is not present in said chemical formulation.
16. A method for fabricating a semiconductor wafer which includes the steps comprising:
cleaning said wafer using a chemical formulation comprising at least one organic chelating agent and at least two polar solvents wherein the organic chelating agent and polar solvents are in sufficient amounts to effectively remove residues from a semiconductor wafer, wherein said chemical formulation is free from components selected from the group consisting of strong inorganic acids, strong bases, amine-containing components, and catalysts,
wherein the chemical formulation is selected from the group consisting of:
a. Malonic acid from about 5% to about 10;
CHP from about 20% to about 75%; and
Water from about 20% to about 40%; and
b. Malonic acid from about 5% to about 10%;
1,4-Butanediol from about 20% to about 75%; and
Water from about 20% to about 40%.
17. The method according to claim 16 wherein the wafer is exposed to said chemical formulation for a period of 15-60 minutes at a temperature range of 45-75° C.
18. A method for preparing a chemical formulation for cleaning residue from a semiconductor wafer after an ashing process, the method comprising:
preparing a formulation comprising at least one organic chelating agent and at least two polar solvents combined in a sufficient amount to effectively remove substantially all residue from the semiconductor wafer, wherein said chemical formulation is free from components selected from the group consisting of strong inorganic acids, strong bases, amine-containing components, and catalysts, and wherein the at least two polar solvents comprise water and at least one organic solvent selected from the group consisting of Cyclohexylpyrrolidone (CUP) and 1,4-Butanediol.
19. The method according to claim 18 wherein the amounts of the organic chelating agent and said at least two polar solvents range from about 2% to about 98%.
20. The method according to claim 18 wherein the organic chelating agent in the percentage by weight range shown is selected from the group consisting of: 2,4-Pentanedione 0.01-98%, Malonic acid 0.01-10%, Oxalic acid 0.01-5%, p-Toluenesulfonic acid 0.01-10%, and Trifluoroacetic acid 0.01-12%.
21. The method according to claim 18 wherein the amount of water in percent by weight, based on the total weight of the formulation, is from 0.01% to 98%.
22. The method according to claim 20 wherein the amount of the at least one organic solvent in percent by weight, based on the total weight of the formulation, is selected from the group consisting of: Cyclohexylpyrrolidone (CHP) 0.01-75% and 1,4-Butanediol 0.01-75%.
23. The method according to claim 18 Wherein sulfonic acid is not present in said chemical formulation.
24. The method according to claim 18 wherein the residue is an inorganic compound.
25. A method for preparing a chemical formulation for cleaning residue from a semiconductor wafer alter an ashing process, the method comprising:
combining at least one organic chelating agent and at least two polar solvents in a sufficient amount to effectively remove substantially all residue from the semiconductor wafer, wherein said chemical formulation is free from components selected from the group consisting of strong inorganic acids, strong bases, amine-containing components, and catalysts,
a. Malonic acid from about 5% to about 10%;
CHP from about 20% to about 75%; and
Water from about 20% to about 40% and
b. Malonic acid from about 5% to about 10%;
1,4-Butanediol from about 20% to about 75%; and
Water from about 20% to about 40%.
26. The cleaning formulation according to claim 1 wherein the organic chelating agent comprises malonic acid.
27. The cleaning formulation according to claim 1 wherein the at least one organic solvent comprises 1,4-Butanediol.
28. The method according to claim 9 wherein the organic chelating agent comprises malonic acid.
29. The method according to claim 9 wherein the at least one organic solvent comprises 1,4-Butanediol.
30. The method according to claim 18 wherein the organic chelating agent comprises malonic acid.
31. The method according to claim 18 wherein the at least one organic solvent comprises 1,4-Butanediol.
32. The cleaning formulation according to claim 1 having a pH in a range from 1.5 to 6.9.
33. The cleaning formulation according to claim 1 wherein the organic chelating agent comprises 2,4-pentanedione.
34. The cleaning formulation according to claim 1 wherein the organic chelating agent comprises p-toluenesulfonic acid.