PROCESS FOR REMOVING COPPER FILMS FROM PRINTED WAFERS OR CIRCUIT BOARDS WITH ELECTROLYSIS RECOVERY OF THE COPPER CONTAINED IN THE CAUSTIC SOLUTION

摘要

P A PROCESS FOR THE REMOVAL OF COPPER FILMS FROM PRINTED WAFERS OR CIRCUIT BOARDS 24 IS USED BY USING AN AMMONIACAL COPPER SULFATE SOLUTION, FOLLOWING WHICH THE CAUSTIC SOLUTION CONTAINS ALSO A CONTAINING SUBSTANCE BROMINE AS A CATALYST FOR INCREASING ATTACK OR REMOVAL SPEED, ESPECIALLY NHBR OR CHCHBRCOBR. SUCH A CAUSTIC SOLUTION ALLOWS THE ELECTROLYTIC SEPARATION OF DUCTILE COPPER FOLLOWING A COHERENT LAYER, EASILY DETACHABLE FROM SPECIAL STEEL ELECTRODES. /P