Patent ID: 8828878

Claim:
A manufacturing method for a dual damascene structure, comprising steps of: providing a substrate having at least a dielectric layer, a first hard mask layer, a first cap layer, a second hard mask layer, and a second cap layer sequentially formed thereon; performing a first double patterning process to sequentially form a plurality of first trench openings and a plurality of second trench openings in the second cap layer and the second hard mask and expose the first cap layer, wherein the first trench openings respectively comprise a first end of the first trench opening and a second end of the first trench opening, and the second trench openings respectively comprise a first end of the second trench opening and a second end of the second trench opening; performing a second double patterning process to sequentially form a plurality of first via openings and a plurality of second via openings in the first cap layer and the first hard mask layer; and transferring the first trench openings, the second trench openings, the first via openings, and the second via openings to the dielectric layer to form a plurality of dual damascene openings.