a semiconductor stack comprising a first semiconductor layer, a second semiconductor layer and an active area between the first semiconductor layer and the second semiconductor layer, wherein the first semiconductor layer comprising an upper surface;

multiple exposed regions formed in the semiconductor stack to expose the upper surface, wherein in a top view, the multiple exposed regions are disposed in an inner region of the semiconductor stack;

a first reflective structure formed on the second semiconductor layer and comprising multiple openings and a periphery surrounding the multiple openings, wherein in the top view, a shortest gap between one of the multiple openings and one of the multiple exposed regions is d1, and a shortest gap between two adjacent openings of the multiple openings is d2, and d1 is greater than d2;

a second metal reflective structure formed on the first reflective structure, filled in the multiple openings, and electrically connected to the second semiconductor layer; and

a first protective layer covering the multiple exposed regions and a portion of the second semiconductor layer, and directly and physically contacting the semiconductor stack, wherein the first protective layer comprises an end portion contacting the upper surface and extending beyond a portion of the periphery of the first reflective structure in a cross-sectional view;

wherein the first reflective structure comprises dielectric material.