Abstract: Semiconductor wafers have ashed photoresist residue and/or post-etch residue thereon to be cleaned through the chemical wet station, and a pattern of exposed metal layer. Post-etch residue removing solvent such as EKC-270 is fed into the solvent tank through a first solvent valve and first liquid feeding conduit that connected to bottom of the solvent tank. A circulation conduit connects the solvent tank with the first liquid feeding conduit for circulating the post-etch residue removing solvent. A liquid feeding pump is connected with the first liquid feeding conduit. A liquid drain conduit and a drain valve are connected with bottom of the solvent tank. Replacement solvent such as EKC-800 is fed into the solvent tank through a second solvent valve and second liquid feeding conduit.

Abstract: Semiconductor wafers have ashed photoresist residue and/or post-etch residue thereon to be cleaned through the chemical wet station, and a pattern of exposed metal layer. Post-etch residue removing solvent such as EKC-270 is fed into the solvent tank through a first solvent valve and first liquid feeding conduit that connected to bottom of the solvent tank. A circulation conduit connects the solvent tank with the first liquid feeding conduit for circulating the post-etch residue removing solvent. A liquid feeding pump is connected with the first liquid feeding conduit. A liquid drain conduit and a drain valve are connected with bottom of the solvent tank. Replacement solvent such as EKC-800 is fed into the solvent tank through a second solvent valve and second liquid feeding conduit.