Patent ID: 6855634

Claim:
A polishing method for polishing a film of an object to be polished having a substrate, an insulating film formed over the substrate, interconnection grooves formed in the insulating film, and an interconnection layer film, formed inside and outside of the interconnection grooves comprising: supplying a processing solution over the surface to be polished at least substantially parallel to that surface and removing by polishing the interconnection film formed outside of the interconnection grooves by a shear stress due to the processing solution; wherein the object to be polished is an object having contact holes communicating with the interconnection grooves formed in the insulating film and having portions of an interconnection layer formed buried inside the contact holes as well; using a processing solution containing at least a chelating agent as the processing solution; chelating the surface part of the film by the chelating agent to form a chelate film; removing by polishing preferentially projecting portions of the chelate film by the shear stress of the processing solution; and repeatedly again forming a chelate film on the surface parts of the film exposed at the projecting portions and removing by polishing preferentially the projecting portions of the chelate film to flatten the film.