Light emitting device
A light emitting diode chip having improved light extraction efficiency is provided. The light emitting diode chip includes a substrate, a first conductivity type semiconductor layer, a mesa, a side coating layer, and a reflection structure. The first conductivity type semiconductor layer is disposed on the substrate. The mesa includes an active layer and a second conductivity type semiconductor layer. The mesa is disposed on a partial region of the first conductivity type semiconductor layer to expose an upper surface of the first conductivity type semiconductor layer along an edge of the first conductivity type semiconductor layer. The side coating layer(s) covers a side surface of the mesa. The reflection structure is spaced apart from the side coating layer(s) and disposed on the exposed first conductivity type semiconductor layer.
1 . A light emitting device comprising:
a first conductivity type semiconductor layer including a first surface and a second surface that is opposite to the first surface;
a second conductivity type semiconductor layer;
an active layer disposed between the first conductivity type semiconductor layer and the second conductivity type semiconductor layer; and
a side coating layer covering side surfaces of the active layer and the second conductivity type semiconductor layer,
wherein the active layer and the second conductivity type semiconductor layer are disposed on a partial region of the first conductivity type semiconductor layer to expose at least a portion of the first surface of the first conductivity type semiconductor layer,
wherein the at least the portion of the first surface of the first conductivity type semiconductor layer has a region having a first horizontal elevation and a region having a second horizontal elevation lower than the first horizontal elevation, and
wherein the first conductivity type semiconductor layer has a roughened region on a portion of the second surface that is opposite to the region having the first horizontal elevation.
2 . The light emitting device of claim 1 , wherein a distance between the region having the second horizontal elevation and the roughened region is smaller than a distance between the region having the first horizontal elevation and the roughened region.
3 . The light emitting device of claim 1 , further comprising a reflection structure spaced apart from the side coating layer and disposed on the at least the portion of the first surface of the first conductivity type semiconductor layer.
4 . The light emitting device of claim 3 , wherein the region having the second horizontal elevation is disposed between an end portion of the side coating layer and an end portion of the reflection structure.
5 . The light emitting device of claim 1 , wherein the side coating layer extends from the side surfaces of the active layer and the second conductivity type semiconductor layer to cover the at least the portion of the first surface of the first conductivity type semiconductor layer.
6 . The light emitting device of claim 1 , wherein the side coating layer includes insulation material.
7 . The light emitting device of claim 6 , further comprising: a first metal layer electrically connected to the first conductivity type semiconductor layer and covering the insulation material.
8 . A light emitting device comprising:
a first conductivity type semiconductor layer including a first surface and a second surface that is opposite to the first surface;
a second conductivity type semiconductor layer;
an active layer disposed between the first conductivity type semiconductor layer and the second conductivity type semiconductor layer; and
a side coating layer covering a side surface of the active layer and the second conductivity type semiconductor layer,
wherein the active layer and the second conductivity type semiconductor layer are disposed on a partial region of the first conductivity type semiconductor layer to expose at least a portion of the first surface of the first conductivity type semiconductor layer,
wherein the at least the portion of the first surface of the first conductivity type semiconductor layer has a region having a first horizontal elevation and a region having a second horizontal elevation lower than the first horizontal elevation, and
wherein the first conductivity type semiconductor layer has a roughened region on a portion of the second surface that is opposite to the region having the second horizontal elevation.
9 . The light emitting device of claim 8 , wherein a distance between the region having the second horizontal elevation and the roughened region is smaller than a distance between the region having the first horizontal elevation and the roughened region.
10 . The light emitting device of claim 8 , further comprising a reflection structure spaced apart from the side coating layer and disposed on the at least the portion of the first surface of the first conductivity type semiconductor layer.
11 . The light emitting device of claim 10 , wherein the region having the second horizontal elevation is disposed between an end portion of the side coating layer and an end portion of the reflection structure.
12 . The light emitting device of claim 8 , wherein the side coating layer extends from side surfaces of the active layer and the second conductivity type semiconductor layer to cover the at least the portion of the first surface of the first conductivity type semiconductor layer.
13 . The light emitting device of claim 8 , wherein the side coating layer includes insulation material.
14 . The light emitting device of claim 13 , further comprising: a first metal layer electrically connected to the first conductivity type semiconductor layer and covering the insulation material.