Samsung patents stacked LED design for brighter screens at lower voltage

1. A light-emitting device comprising: a light-emitting portion comprising a first light-emitting structure and a second light-emitting structure on the first light-emitting structure in a first direction, the first light-emitting structure and the second light-emitting structure configured to emit light of a same wavelength as each other, wherein a width of the second light-emitting structure is greater than a width of the first light-emitting structure, each of the first light-emitting structure and the second light-emitting structure comprises a first conductivity type semiconductor layer, an active layer, and a second conductivity type semiconductor layer, and the active layer is between the first conductivity type semiconductor layer and the second conductivity type semiconductor layer in the first direction; a first common electrode comprising: a first common portion under the light-emitting portion in a second direction opposite to the first direction; and a plurality of first electrode portions extending from the first common portion such as to respectively contact the first conductivity type semiconductor layer of the first light-emitting structure and the first conductivity type semiconductor layer of the second light-emitting structure, wherein at least one of the plurality of first electrode portions comprises a conductive via structure; a second common electrode comprising: a second common portion under the light-emitting portion in the second direction; and a plurality of second electrode portions extending from the second common portion in the first direction such as to respectively contact a side surface of the second conductivity type semiconductor layer of the first light-emitting structure and a side surface of the second conductivity type semiconductor layer of the second light-emitting structure, wherein the plurality of second electrode portions are spaced apart from each other in a third direction crossing the first direction; and a plurality of separation layers configured to insulate the side surface of the second conductivity type semiconductor layer of the first light-emitting structure, the side surface of the second conductivity type semiconductor layer of the second light-emitting structure, a side surface of the active layer of the first light-emitting structure, and a side surface of the active layer of the second light-emitting structure from the plurality of second electrode portions.