Method for fabricating semiconductor device

A method for fabricating a semiconductor device, comprising:

• forming a plurality of openings in a first film;
• embedding a metallic material serving as both a plug material and an alignment mark material for alignment with an upper layer in the plurality of openings;
• forming a second film on the first film in which the metallic material is embedded;
• irradiating the second film formed in a predetermined region including a position where the metallic material is embedded as the alignment mark material with a processing light, thereby to remove the second film to an extent that a portion of the second film remains in the predetermined region;
• and
• etching, by wet etching method, the portion of the second film remaining in the predetermined region and not having been removed by controlling that the portion of the second film remains in the predetermined region in the irradiating.