Patent ID: 8217454

Claim:
A semiconductor device, comprising: a substrate, having a first conductive type and having an active device region and a peripheral region surrounding the active device region defined thereon; an epitaxial layer, having the first conductive type and disposed on the substrate; at least one first semiconductor layer, having a second conductive type, and disposed in the epitaxial layer of the peripheral region, the first semiconductor layer having an arc portion, a first strip portion extending out from an end of the arc portion, and a second strip portion extending out from the other end of the arc portion, wherein the first strip portion points to the active device region, and the second strip portion is perpendicular to the first strip portion; and a second semiconductor layer, having the second conductive type, disposed in the epitaxial layer of the peripheral region between the active device region and the second strip portion, and the second semiconductor layer having a first sidewall and a second sidewall opposite to the first sidewall, the first facing the first semiconductor layer, wherein the first sidewall is parallel to the first semiconductor layer, and a first distance is between the first sidewall and the first semiconductor layer.