Abstract: A semiconductor device includes a semiconductor stack, a reflective structure, and a conductive structure. The semiconductor stack includes a first semiconductor structure, a second semiconductor structure and an active region located between the first semiconductor structure and the second semiconductor structure. The reflective structure is located at a side of semiconductor stack closed to the first semiconductor structure, and includes a first metal. The conductive structure locates between the reflective structure and the first semiconductor structure, and includes a first region overlapping with the active structure and a second region which does not overlap with the active structure. The first metal in the second region has a concentration smaller than 5 atomic percent.