A semiconductor device manufacturing method includes removing copper deposits, by use of an organic acid gas and an oxidizing gas, from a surface of a second interlayer insulation film having a groove formed therein and reaching a copper-containing electric connector member. The second interlayer insulation film is disposed on a first interlayer insulation film provided with the electric connector member. The method then includes reducing a surface of the electric connector member exposed at a bottom of the groove of the second interlayer insulation film; forming a barrier layer on the second interlayer insulation film; and forming a copper-containing conductive film to fill the groove of the second interlayer insulation film.