purposes only first workpiece cleaning apparatus 102 a may use anionic sponges not shown and workpiece cleaning fluid of approximately 2 ammonium hydroxide solution ph about 11 to clean a semiconductor wafer after cmp anionic sponges may then be cleaned in first sponge cleaning station 108 a with a sponge cleaning fluid of approximately 2 ammonium hydroxide solution after this initial cleaning the workpiece may be transferred via robot 112 to second workpiece cleaning apparatus 102 b second workpiece cleaning apparatus 102 b may use cationic sponges also not shown with a workpiece cleaning fluid containing a sponge charge modifying agent such as polyethylamine an aliphatic amine such a fluid may have a ph of approximately 8 at ph 8 cationic brushes may have a positive charge and thus attract negatively charged particles and repel positively charged particles from the surface of the workpiece cationic sponges may then be cleaned in second sponge cleaning apparatus with approximately 2 ammonium hydroxide solution as the sponge cleaning fluid at ph approximately 11 caused by the ammonium hydroxide solution the cationic brushes may acquire a negative charge and thus negatively charged particles formerly adhering to the surface of the sponges may no longer be attracted to their surfaces and may easily fall off or be easily washed off the above described systems and methods for cleaning workpiece and for cleaning sponges using variations in sponge surface charges and cleaning fluids achieve the desired results of more effectively cleaning workpieces and more effectively cleaning sponges the overall result is a higher yield on workpieces such as semiconductor wafers and sponges that have longer longevity and work.