A light-emitting device, includes a substrate, including an upper surface; a first light emitting unit and a second light emitting unit, formed on the upper surface, wherein each of the first light emitting unit and the second light emitting unit includes a lower semiconductor portion and an upper semiconductor portion; and a conductive structure electrically connecting the first light emitting unit and the second light emitting unit; wherein the lower semiconductor portion of the first light emitting unit includes a first sidewall and a first upper surface; and wherein the first side wall includes a first sub-side wall and a second sub-side wall, an obtuse angle is formed between the first sub-side wall and the first upper surface and another obtuse angle is formed between the second sub-side wall and the upper surface.