Light emitting element, manufacturing method of light emitting element, and display device including light emitting element
A light emitting element includes: a first semiconductor layer including a semiconductor of a first type; a second semiconductor layer including a semiconductor of a second type different from the first type; and an active layer between the first and second semiconductor layers, the active layer including a first active area including a first well layer, and a second active area including a second well layer. The first well layer has a first band gap, and the second well layer has a second band gap smaller than the first band gap. At least a portion of the first active area is between the second active area and the second semiconductor layer. A distance between the second active area and the second semiconductor layer is equal to or greater than 0.1 times of a distance between the first and second semiconductor layers.
1 . A light emitting element comprising:
a first semiconductor layer comprising an N-type semiconductor;
a second semiconductor layer comprising a P-type semiconductor; and
an active layer between the first semiconductor layer and the second semiconductor layer, the active layer comprising a first active area comprising a first well layer, and a second active area comprising a second well layer,
wherein the first well layer has a first band gap, and
the second well layer has a second band gap smaller than the first band gap,
wherein at least a portion of the first active area is between the second active area and the second semiconductor layer,
wherein the second active area is spaced apart from the first semiconductor layer at a first distance, and is spaced apart from the second semiconductor layer at a second distance, the second distance being smaller than the first distance,
wherein the second distance is equal to or greater than 0.1 times of a distance between the first semiconductor layer and the second semiconductor layer,
wherein the first distance is 0.2 times to 0.35 times the height of the active layer and the second distance is 0.2 times to 0.25 times the height of the active layer,
wherein the active layer comprises band-gap-determining material,
wherein an atomic ratio of the band-gap-determining material in the first active area is equal to or greater than a first atomic ratio,
wherein an atomic ratio of the band-gap-determining material in the second active area is equal to or greater than a second atomic ratio, the second atomic ratio being greater than the first atomic ratio,
wherein the first active area comprises a (1-1)th active area and a (1-2)th active area,
wherein the (1-1)th active area is between the first semiconductor layer and the second active area,
wherein the (1-2)th active area is between the second semiconductor layer and the second active area, and
wherein the (1-1)th active is directly adjacent to the first semiconductor layer and the (1-2)th active are is directly adjacent to the second semiconductor layer.
2 . The light emitting element of claim 1 , wherein light having a first wavelength is to be emitted in the first active area, and
light having a second wavelength greater than the first wavelength is to be emitted in the second active area.
3 . The light emitting element of claim 1 , wherein the second distance is 0.2 times to 0.25 times of the distance between the first semiconductor layer and the second semiconductor layer.
4 . The light emitting element of claim 3 , wherein the first distance is equal to or greater than 0.2 times of the distance between the first semiconductor layer and the second semiconductor layer.
5 . The light emitting element of claim 1 , wherein a ratio of the second distance to the first distance is 0.55 to 1.
6 . The light emitting element of claim 1 , wherein a ratio of the second distance to the first distance is 0.8 to 1.25.
7 . The light emitting element of claim 1 , wherein the second atomic ratio is equal to or greater than 10%.
8 . The light emitting element of claim 7 , wherein the band-gap-determining material comprises indium (In).
9 . A method of manufacturing a light emitting element, the method comprising:
providing, on a stack substrate, a first semiconductor layer comprising an N-type semiconductor;
providing an active layer on the first semiconductor layer; and
providing, on the active layer, a second semiconductor layer comprising a P-type semiconductor,
wherein the providing of the active layer comprises:
providing a first well layer; and
providing a second well layer, at least a portion of the first well layer being between the second well layer and the second semiconductor layer,
wherein an energy band gap of the second well layer is smaller than an energy band gap of the first well layer,
wherein the active layer comprises a first active area comprising the first well layer, and a second active area comprising the second well layer,
wherein the second active area is spaced apart from the first semiconductor layer at a first distance, and is spaced apart from the second semiconductor layer at a second distance, the second distance being smaller than the first distance,
wherein the second distance is equal to or greater than 0.1 times of a distance between the first semiconductor layer and the second semiconductor layer,
wherein the first distance is 0.2 times to 0.35 times the height of the active layer and the second distance is 0.2 times to 0.25 times the height of the active layer
wherein the active layer comprises band-gap-determining material,
wherein an atomic ratio of the band-gap-determining material in the first active area is equal to or greater than a first atomic ratio,
wherein an atomic ratio of the band-gap-determining material in the second active area is equal to or greater than a second atomic ratio, the second atomic ratio being greater than the first atomic ratio,
wherein the first active area comprises a (1-1)th active area and a (1-2)th active area,
wherein the (1-1)th active area is between the first semiconductor layer and the second active area,
wherein the (1-2)th active area is between the second semiconductor layer and the second active area, and
wherein the (1-1)th active is directly adjacent to the first semiconductor layer and the (1-2)th active are is directly adjacent to the second semiconductor layer.
10 . The method of claim 9 , wherein light having a first wavelength is to be emitted in the first active area, and
light having a second wavelength greater than the first wavelength is to be emitted in the second active area.
11 . The method of claim 9 , further comprising etching the first semiconductor layer, the active layer, and the second semiconductor layer,
wherein the providing of the first well layer further comprises:
providing a (1-1)th well layer on the first semiconductor layer; and
providing a (1-2)th well layer on the second well layer,
wherein the second well layer is between the (1-1)th well layer and the (1-2)th well layer, and
wherein the etching is performed after the providing of the (1-2)th well layer.
12 . The method of claim 11 , wherein the etching is performed in a direction toward the (1-1)th well layer from the (1-2)th well layer.
13 . The method of claim 1 , wherein the second distance is 0.2 times to 0.25 times of the distance between the first semiconductor layer and the second semiconductor layer.
14 . The method of claim 13 , wherein the first distance is equal to or greater than 0.2 times of the distance between the first semiconductor layer and the second semiconductor layer.
15 . The method of claim 9 , wherein the active layer comprises band-gap-determining material, and
wherein an atomic ratio of the band-gap-determining material in the first active area is smaller than an atomic ratio of the band-gap-determining material in the second active area.
16 . An electronic device comprising the light emitting element according to claim 1 .