A semiconductor manufacturing apparatus capable of removing metal derived from an electrode from ozone generated by the silent discharge is provided. The ozone generated by the silent discharge between electrodes in the ozone generating unit is permeated through a molecule permeable film based on pressure difference between the back and the front of the molecule permeable film constituting a filter. The permeated ozone is supplied together with separately-generated water vapor to a resist surface on a semiconductor wafer to remove the resist. In the resist removal described above, the high-concentration metal contamination due to the metal derived from an electrode can be prevented.