Method for removing copper residue from surfaces of a semiconductor wafer

摘要

A method for effectively removing copper residue from surfaces of a semiconductor wafer includes the step of immersing the semiconductor wafer having the copper residue into an acidic solution and then into a basic cleaning solution. The acidic solution includes hydrogen fluoride (HF) and hydrogen chloride (HCl) for breaking bonds within the copper residue which may include for example dicopper oxide (Cu2O), copper oxide (CuO), and organic copper residue such as copper benzotriazole (Cu-BTA complex). The basic cleaning solution includes tetramethylammonium hydroxide ((CH3)4NOH) and surfactant (RE-610) for effectively acting as an emulsifier to rinse away the copper residue having broken bonds from the semiconductor wafer. The present invention may be practiced to particular advantage when the semiconductor wafer is immersed in deionized water after immersion in the acidic solution and after immersion in the basic cleaning solution.