Photoresist and post etch residue cleaning solution

1. There is provided a solution comprising:

A. a polar aprotic solvent,

B. an inorganic base;

C. a co-solvent for said inorganic base;

D. a unsaturated cycloaliphatic compound having a ring ether group and at least one substituent bearing a primary hydroxyl group;

E. an organic base comprising an amine compound;

F. a nonionic surfactant bearing at least one ether group; and

G. water present in an amount less than 2 wt. %.

2. The solution of claim 1 , wherein the polar aprotic solvent comprises a C 1 -C 4 dialkyl sulfoxide.

3. The solution of claim 2 , wherein the polar aprotic solvent comprises dimethyl sulfoxide.

4. The solution of claim 2 , wherein the solution contains less than 8 weight percent pyrrolidone compounds.

5. The solution of claim 4 , wherein the solution contains less than 3 weight percent pyrrolidone compounds.

6. The solution of claim 5 , wherein the solution contains no added pyrrolidone compounds.

7. The solution of claim 3 , wherein dimethyl sulfoxide is present in an amount within a range of 60 wt. % to 90 wt. %.

8. The solution of claim 7 , wherein dimethyl sulfoxide is present in an amount within a range of 75 wt. % to 85 wt. %.

9. The solution of claim 1 , wherein the polar aprotic solvent is a type present in an amount effective to remove:

(i) uncured polyimide photoresist from a semiconductor wafer and

(ii) polyimide polymer residues that have been subjected to a plasma etching process,

at one or more temperatures within a range of 78° C. to 90° C. and within 30 seconds when immersed in the solution.

10. The solution of claim 1 , wherein the inorganic base comprises a hydroxide of a Group I or Group II metal.

11. The solution of claim 10 , wherein the inorganic base comprises a hydroxide of a Group I metal.

12. The solution of claim 11 , wherein the inorganic base comprises potassium hydroxide.

13. The solution of claim 1 , wherein the solution does not precipitate solids containing the metal of the inorganic base upon heating to 93° C. and within a 4 hour cool down period in ambient conditions.

14. The solution of claim 1 , wherein the inorganic base comprises potassium hydroxide present in an amount of at least 1.0 wt. % up to 2.5 wt. %.

15. The solution of claim 14 , wherein the inorganic base comprises potassium hydroxide in an amount greater than 1.0 wt. % up to 2.0 wt. %.

16. The solution of claim 1 , wherein the inorganic base comprises a compound that reacts with a polyimide polymer on a semiconductor wafer within 30 seconds at one or more temperatures within a range of 78° C. to 90° C.

17. The solution of claim 1 , wherein the solution does not contain added lithium hydroxide.

18. The solution of claim 1 , wherein the co-solvent comprises a compound that solvates said inorganic base in the polar aprotic solvent.

19. The solution of claim 1 , wherein the co-solvent comprises a glycol ether compound having at least one ether group and at least one hydroxyl group.

20. The solution of claim 19 , wherein the glycol ether has a molecular weight of less than 200.

21. The solution of claim 20 , wherein the glycol ether has a molecular weight of less than 150.

22. The solution of claim 1 , wherein the co-solvent comprises a glycol ether having one ether group and one hydroxyl group.

23. The solution of claim 22 , wherein the co-solvent is represented by a compound having a structure comprising:

R4′—C02C2H4OC2H4—OR4,  (II)

R5′—C02C3H6OC3H6—OR5  (III)

R6OC02R7  (IV)

R8OC2H4OC2H4OH,  (V)

R9OC3H6OC3H6OH,  (VI)

R10OC2H4OH, or  (VII)

R11OC3H6OH,  (VIII)

wherein R4, R4′, R5, R5′, R6, R7, R8, R9, R10, and R11 are independently selected from C1-C14-alkyl groups; wherein R and R1 may be selected from C1 to C8 alkyl groups, but with the provision that both R and R1 cannot represent a methyl group.

24. The solution of claim 1 , wherein the co-solvent comprises ethyleneglycol monomethyl ether, ethyleneglycol monoethyl ether, propylene glycol monomethyl ether, diethylene glycol monomethyl ether, diethylene glycol monoethyl ether, diethylene glycol monopropyl ether, diethylene glycol monobutyl ether, dipropylene glycol monobutyl ether, dipropylene glycol monopropyl ether, tripropylene glycol monomethyl ether, tripropylene glycol monobutyl ether, propyleneglycol butyl ether, ethylene glycol monohexyl ether, ethyleneglycol mono-2-ethylbuyl ether, triethyleneglycol monobutyl ether, tetraethyleneglycol monobutyl ether, or tetrapropyleneglycol monobutyl ether.

25. The solution of claim 1 , wherein the co-solvent comprises a compound represented by the following formula (IX):

wherein R1 and R3 are each independently a hydrogen atom or a C1-C4 alkyl group, and R2 is a C1-C4 alkyl group.

26. The solution of claim 1 , wherein the co-solvent comprises 3-methoxybutanol; 3-methyl-3-methoxybutanol; or 3-methyl-1,3-butanediol.

27. The solution of claim 1 , wherein the co-solvent comprises 3-methyl-3-methoxybutanol, 3-methoxybutanol, or a combination thereof.

28. The solution of claim 1 , wherein the co-solvent comprises a compound represented by the following general formula (I):

R12O(C2H4)m(C3H6O)nR13

wherein R12 and R13 each individually are a hydrogen atom or an alkyl group having 1-8 carbon atoms, provided that R12 and R13 are not both hydrogen atoms, m and n stand individually for an integer of 0-10 provided that m plus n does not equal zero.

29. The solution of claim 1 , wherein the co-solvent is present in the solution in an amount of up to 15 wt. %.

30. The solution of claim 29 , wherein the co-solvent is present in the solution in an amount of at least 4 wt. % and up to 8 wt. %.

31. The solution of claim 1 , wherein said unsaturated cycloaliphatic compound comprises a compound represented by the following general formula (X):

wherein R14 and R15 are independently hydrogen, a hydroxyl group, or a C1-C8 alkyl group having one or more primary or secondary hydroxyl groups, provided that R14 and R15 are not both hydrogen and are not both hydroxyl groups.

32. The solution of claim 1 , wherein said unsaturated cycloaliphatic compound comprises tetrahydrofurfuryl alcohol, furfuryl alcohol, or a combination thereof.

33. The solution of claim 1 , wherein said unsaturated cycloaliphatic compound is effective to remove residues on the tops of solder bumps on a semiconductor wafer subjected to plasma etching.

34. The solution of claim 1 , wherein the unsaturated cycloaliphatic compound is present in the solution in an amount ranging from 1 wt. % to 8 wt. %.

35. The solution of claim 1 comprising

A. dimethyl sulfoxide,

B. potassium hydroxide,

C. a co-solvent represented by the following formula (IX):

wherein R1 and R3 are each independently be a hydrogen atom or a C1-C4 alkyl group, and R2 is a C1-C4 alkyl group,

D. a cycloaliphatic compound having a furfuryl moiety,

E. an alkanolamine,

F. a polyoxyethylene of phenol or an alkylphenol.

36. The solution of claim 1 , wherein the unsaturated cycloaliphatic compound is present in the solution in an amount ranging from 2 wt. % to 5 wt. %.

37. The solution of claim 1 , wherein the organic base comprises an alkanolamine.

38. The solution of claim 37 , wherein the alkanolamine has at least two carbon atoms, at least one nitrogen atom, and at least one hydroxyl group, the nitrogen atom and hydroxyl group being attached to different carbon atoms.

39. The solution of claim 1 , wherein the organic base comprises ethanolamine, N-methylethanolamine, N-ethylethanolamine, N-propylethanolamine, N-butylethanolamine, diethanolamine, triethanolamine, N-methyldiethanolamine, N-ethyldiethanolamine, isopropanolamine, diisopropanolamine, triisopropanolamine, N-methylisopropanolamine, N-ethylisopropanolamine, N-propylisopropanolamine, 2-aminopropane-1-ol, N-methyl-2-aminopropane-1-ol, N-ethyl-2-aminopropane-1-ol, 1-aminopropane-3-ol, N-methyl-1-aminopropane-3-ol, N-ethyl-1-aminopropane-3-ol, 1-aminobutane-2-ol, N-methyl-1-aminobutane-2-ol, N -ethyl-1-aminobutane-2-ol, 2-aminobutane-1-ol, N -methyl-2-aminobutane-l-ol, N-ethyl-2-aminobutane-1-ol, 3-aminobutane-1-ol, N-methyl-3-aminobutane-1-ol, N-ethyl-3-aminobutane-1-ol, 1-aminobutane-4-ol, N-methyl-1-aminobutane-4-ol, N-ethyl-1-aminobutane-4-ol, 1-amino-2-methylpropane-2-ol, 2-amino-2-methylpropane-1-ol, 1-aminopentane-4-ol, 2-amino-4-methylpentane-1-ol, 2-aminohexane-1-ol, 3-aminoheptane-4-ol, 1-aminooctane-2-ol, 5-aminooctane-4-ol 1-aminopropane-2,3-diol, 2-aminopropane-1, 3-diol tris(oxymethyl)aminomethane, 2-(2-aminoethoxy)ethanol, or ethers of alkanolamines.

40. The solution of claim 1 , wherein the organic base comprises ethanolamine, N-methylethanolamine, N-ethylethanolamine, N-propylethanolamine, diethanolamine, triethanolamine, N-methyldiethanolamine, N-ethyldiethanolamine, isopropanolamine, or diisopropanolamine.

41. The solution of claim 1 , wherein the organic base comprises N-methylethanolamine.

42. The solution of claim 1 , wherein the organic base is present in an amount ranging from 1 wt. % to 5 wt. %.

43. The solution of claim 1 , wherein the organic base is present in an amount ranging from 1.5 wt. % to 4 wt. %.

44. The solution of claim 1 , wherein the organic base comprises an alkanolamine that is liquid at 25° C.

45. The solution of claim 1 , wherein the nonionic surfactant has an HLB number of at least 8.

46. The solution of claim 1 , wherein the surfactant has a molecular weight of greater than 200 and less than 1000.

47. The solution of claim 1 , wherein the surfactant is a liquid and has a viscosity of less than 200 cps at 25° C.

48. The solution of claim 1 , wherein the surfactant has a viscosity of less than 100 centipoise at 25° C.

49. The solution of claim 1 , wherein the amount of surfactant is at least 1 wt. % and up to 10 wt. %.

50. The solution of claim 1 , wherein the surfactant has a molecular weight of less than 800.

51. The solution of claim 1 , wherein the surfactant comprises an aromatic ring having at least one substituent, said substituent containing —(C2H4O)— moieties.

52. The solution of claim 1 , wherein the surfactant comprises a compound having a phenolic ethoxylate moiety.

53. The solution of claim 1 , wherein the surfactant comprises an aromatic ring having at least one substituent, said substituent containing —(C2H4O) p — moieties, wherein p is an integer within a range of 1 to 40.

54. The solution of claim 1 , wherein the surfactant comprises an aromatic ring having at least one substituent, said substituent containing —(C2H4O) p — moieties, wherein p is an integer within a range of 2 to 8.

55. The solution of claim 1 , wherein the surfactant comprises an aromatic ring having a first substituent containing —(C2H4O)— moieties and a second substituent comprising a branched or unbranched, saturated or unsaturated, C 1 -C 22 alkyl group.