FlexClean DM is a powerful, non-foaming and free rinsing alkaline cleaner specifically formulated to clean copper on exposed alkalisensitive substrates including polyimide. It will remove oven baked residues, oxidation, fingerprints and oils, all without attack of alkali sensitive substrates or removal of any copper metal. Use of FlexClean DM will leave the copper surface bright, oxidation-free and ready for photoresist application or oxide process. FlexClean DM may be used in conjunction with an acid cleaner, or if required, a light microetch. If a microetch is used, much lower levels of metal are fully acceptable thus minimizing costs and reject rate.