The present disclosure provides a method of forming a semiconductor structure. The method includes providing a semiconductor substrate and forming a patterned metal structure on the semiconductor substrate, wherein the patterned metal structure includes a first metal layer and a second metal layer deposited in a single deposition step. The method further includes etching a portion of the second metal layer thereby forming a metal plug in the second metal layer, the first metal layer of the patterned metal structure having a first metal feature underlying and contacting the metal plug.