Light emitting device and method of manufacturing the same
A light emitting device having improved light extraction efficiency is disclosed. The light emitting device includes a nitride semiconductor layer including a first semiconductor layer, an active layer, and a second semiconductor layer, which are sequentially stacked, a portion of the first semiconductor layer being exposed to the outside by performing mesa etching from the second semiconductor layer to the portion of the first semiconductor layer, and at least one groove formed through a portion of the first semiconductor layer, the active layer, and the second semiconductor layer.
1. A light emitting device comprising:
a nitride semiconductor layer including a first semiconductor layer, an active layer, and a second semiconductor layer, which are sequentially stacked; and
at least one groove formed through a portion of the first semiconductor layer, the active layer, and the second semiconductor layer,
wherein the portion of the first semiconductor layer, the active layer, and the second semiconductor layer are exposed to the outside by the at least one groove, and
wherein the at least one groove includes a plurality of grooves, the grooves being spaced apart from each other such that I/I 0 is 0.5 or more (where, I is the intensity of light after the light advances a distance L; I=I 0 {exp(−αL)}, I 0 is the initial intensity of the light, and α is the absorption coefficient of the nitride semiconductor layer).
2. The light emitting device according to claim 1 , wherein the at least one groove has a width of 1 to 10 μm.
3. The light emitting device according to claim 1 , wherein the at least one groove is inclined at an angle of 0 to 70 degrees to a line perpendicular to the nitride semiconductor layer.
4. The light emitting device according to claim 1 , wherein the at least one groove is formed in the shape of a stripe.
5. The light emitting device according to claim 1 , further comprising:
a transparent electrode and a second electrode sequentially formed on the second semiconductor layer, wherein
the at least one groove is formed through the transparent electrode.
6. The light emitting device according to claim 5 , wherein the transparent electrode is formed of a dual layer including nickel (Ni) and gold (Au) or a transparent conducting oxide (TCO) layer.
7. The light emitting device according to claim 1 , further comprising a first electrode formed on an exposed portion of the first semiconductor layer.
8. A light emitting device comprising:
a conductive support film;
an ohmic layer on the conductive support film;
a semiconductor layer including a first semiconductor layer, an active layer, and a second semiconductor layer;
an electrode on the semiconductor layer; and
at least one groove formed through at least a portion of the first semiconductor layer or the second semiconductor layer, and through the active layer,
wherein the conductive support film and the electrode are located at opposite sides of the semiconductor layer, respectively, and
wherein the conductive support film covers the at least one groove.
9. The light emitting device according to claim 8 , wherein the at least one groove includes a plurality of grooves, the grooves being spaced apart from each other such that I/I 0 is 0.5 or more (where, I is the intensity of light after the light advances a distance L; I=I 0 {exp(−αL)}, I 0 is the initial intensity of the light, and α is the absorption coefficient of the semiconductor layer).
10. The light emitting device according to claim 8 , wherein the at least one groove has a width of 1 to 10 μm.
11. The light emitting device according to claim 8 , wherein the at least one groove is inclined at an angle of 0 to 70 degrees to a line perpendicular to the semiconductor layer.