A method for forming an integrated device includes following operations. It is provided a first circuit having a first connecting path in a metal line layer, a second connecting path, and a third connecting path. The second connecting path is electrically connected to a first connecting portion of the first connecting path in the metal line layer. The third connecting path is electrically coupled to a second connecting portion of the first connecting path in the metal line layer. An electromigration (EM) data of the first connecting path is analyzed to determine if a third connecting portion in the metal line layer between the first connecting portion and the second connecting portion induces EM phenomenon. The first circuit is modified to generate a second circuit when the third connecting portion induces EM phenomenon. The integrated device is generated according to the second circuit.