A semiconductor device includes a substrate and a chip. The chip stacked on the substrate includes an active surface and at least one metal pad. The metal pad is disposed on the active surface and comprises a first pad portion and a second pad portion separated from the first pad portion to form an open circuit. The first pad portion includes a protrusion structure and the second pad portion includes a recess structure. Moreover, the protrusion structure of the first pad portion extends toward the recess structure of the second pad portion.