SEMICONDUCTOR DEVICE

A semiconductor device includes a semiconductor stack; a substrate formed on the semiconductor stack, including a lower surface connected to the semiconductor stack, an upper surface opposite to the lower surface, and a side surface between the lower surface and the upper surface, wherein the side surface includes a mirror area, a first scribing area, and a first crack area, the mirror area is closer to the lower surface than the first scribing area to the lower surface, and the first scribing area is located between the mirror area and the first crack area; an optical structure on the upper surface of the substrate; and a reflective structure on a side surface of the first scribing area and the first crack area, wherein the first scribing area is arranged below the upper surface of the substrate with a distance less than or equal to ¼ of a thickness of the substrate.