An etching residue removal method includes a cleaning sequence. Preferably, the cleaning sequence has a first washing processing, first drying processing, stripper processing, rinsing processing, second washing processing and second drying processing. In the first washing processing, an insulation film and metal lines thereon are washed by pure water. In the first drying processing, the insulation film and metal lines are dried in a nitrogen atmosphere at room temperature, for example. In the stripper processing, the etching residue on the insulation film and metal lines are stripped by amine stripper, for example. In the rinsing processing, the insulation film and metal lines are rinsed with an IPA rinse solution, for example. In the second washing processing, the insulation film and metal lines are washed with pure water. In the second drying processing, the insulation film and metal lines are dried in the nitrogen atmosphere at room temperature, for example.