A semiconductor device according to the present invention comprises: a conductive substrate; a semiconductor structure disposed on the conductive substrate and comprising a first conductive-type semiconductor layer, a second conductive-type semiconductor layer, and an active layer disposed between the first conductive-type semiconductor layer and the second conductive-type semiconductor layer; and a first electrode disposed on the semiconductor structure and electrically connected to the first conductive-type semiconductor layer, wherein the semiconductor structure further comprises a 1-1 conductive-type semiconductor layer between the first conductive-type semiconductor layer and the first electrode; and the top surface of the semiconductor structure comprises a flat part, on which the first electrode is disposed, and a concave-convex part surrounding the flat part, wherein a second distance, which is from the bottom surface of the semiconductor structure to the bottom surface of the concave-convex part contacting a side surface of the flat part, may be between 70% or more and 95% or less with respect to a first distance, which is from the bottom surface of the semiconductor structure to the top surface of the 1-1 conductive-type semiconductor layer. The present invention may enhance light flux by improving the current spreading phenomenon of the semiconductor device.