Disclosed is a semiconductor device including a semiconductor stack comprising a surface, and an electrode structure comprising an electrode pad formed on the surface, and the electrode structure further comprising a first extending electrode, a second extending electrode and a third extending electrode connecting to the electrode pad. The first extending electrode is closer to a periphery of thesurface than the third extending electrode is, and the second extending electrode is between the first extending electrode and the third extending electrode. From a top view of the semiconductor device, the first extending electrode, the second extending electrode and the third extending electrode respectively include a first curve having a first angle [theta]1, a second curve having a second angle [theta]2 and a third curve having a third angle [theta]3, wherein [theta]3>[theta]2>[theta]1.