An optoelectronic device, comprising a first semiconductor layer comprising four boundaries comprising two longer sides and two shorter sides; a second semiconductor layer formed on the first semiconductor layer; and a plurality of first conductive type electrodes formed on the first semiconductor layer, wherein one first part of the plurality of first conductive type electrodes is formed on a corner constituted by one of the two longer sides and one of the two shorter sides, and wherein one fourth part of the plurality of first conductive type electrodes is formed along the one of the two longer sides, the one fourth part of the plurality of first conductive type electrodes comprises a head portion and a tail portion, the head portion comprises a width larger than that of the tail portion.