Patent ID: 7601605

Claim:
A method for manufacturing a semiconductor device, the method comprising: forming a first dielectric film on a substrate; forming a first conductive film on the first dielectric film; forming a second dielectric film on the first conductive film; etching the second dielectric film to form a first contact hole and an opening section; forming a second conductive film on the second dielectric film such that the first contact hole and the opening section are filled with the second conductive film; and removing a portion of the second conductive film to expose a surface of the second dielectric film where the first contact hole and the alignment mark are not formed, the opening section filled with the second conductive film forming an alignment mark; and forming an oxidation barrier film on the second conductive film to protect the second conductive film from oxidation, wherein the step of removing the portion of the second conductive film includes a chemical mechanical polishing method that removes another portion of the second conductive film located at edges of the opening section such that a step difference between a surface of the second dielectric layer and the alignment mark is minimized.