A method for manufacturing a semiconductor device including forming a first wire on a substrate, forming a lower film on the first wire, forming a photosensitive pattern on the lower film using a photosensitive material, forming contact holes for exposing the first wire by etching the lower film using the photosensitive film as an etching mask, removing part of the photosensitive film pattern by an ashing process to expose a borderline of the lower film defining the contact holes and forming second wire connected to the first wire via the contact holes.