The method includes forming an upper layer on a lower layer, forming a metal interconnection in the upper layer, forming a passivation layer exposing a center part of the metal interconnection on the upper layer, forming a buffer pattern exposing the center part of the metal interconnection, and selectively and asymmetrically covering a peripheral region of the metal interconnect and a part of the passivation layer, forming a wrapping pattern covering the buffer pattern and exposing the center part of the metal interconnection on the passivation layer, and forming a pad pattern on the center part of the metal interconnection.