Patent ID: 7543592

Claim:
A method for removing polymer, etch residue, ash residue, or a combination thereof from a wafer-level packaging substrate, from a printed circuit board, or both, on which a circuit, or a portion of a circuit, is present, which method comprises contacting the wafer-level packaging substrate, the printed circuit board, or both, with a composition, at a temperature and for a time sufficient to remove the polymer, the etch residue, the ash residue, or the combination thereof from the wafer-level packaging substrate, the printed circuit board, or both, while maintaining the operability of the circuit, or portion thereof, associated therewith, wherein the composition comprises (A) an organic ammonium compound having the formula wherein: X is hydroxide, sulfate, hydrogen sulfate, phosphate, hydrogen phosphate, dihydrogen phosphate, nitrate, a carboxylate, a halide, carbonate, hydrogen carbonate, bifluoride, or a combination thereof, R 1 is an alkyl group or a group derived from the reaction of a tertiary amine with an organic epoxy, and R 2 , R 3 , and R 4 are each not hydrogen and are independently alkyl, benzyl, hydroxyalkyl, phenyl, a group derived from the reaction of a tertiary amine with an organic epoxy, or another group contained in a tertiary amine; (B) an oxoammonium compound having the formula wherein: X is hydroxide, sulfate, hydrogen sulfate, phosphate, hydrogen phosphate, dihydrogen phosphate, nitrate, a carboxylate, a halide, carbonate, hydrogen carbonate, bifluoride, or a combination thereof, each R 5 is independently hydrogen, a substituted C 1 -C 6 straight, branched, or cyclic alkyl, alkenyl, or alkynyl group, a substituted acyl group, straight or branched alkoxy group, amidyl group, carboxyl group, alkoxyalkyl group, alkylamino group, alkylsulfonyl group, or sulfonic acid group, phenyl group, substituted phenyl group, aryl group, substituted aryl group, or a salt or derivative thereof, and each R 6 and R 7 is independently hydrogen, a hydroxyl group, a substituted C 1 -C 6 straight, branched, or cyclic alkyl, alkenyl, or alkynyl group, a substituted acyl group, straight or branched alkoxy group, amidyl group, carboxyl group, alkoxyalkyl group, alkylamino group, alkylsulfonyl group, or sulfonic acid group, phenyl group, substituted phenyl group, aryl group, substituted aryl group, or a salt or derivative thereof; (C) water; and (D) an organic polar solvent that is miscible with water, wherein the organic ammonium compound is present in an amount from about 1% to about 30% by weight, the oxoammonium compound is present in an amount from about 2% to about 10% by weight, the water is present in an amount from about 15% to about 94% by weight, and the organic polar solvent is present in an amount from about 25% to about 85% by weight.