Semiconductor light emitting device and fabrication method thereof
A semiconductor light emitting device according to an embodiment includes a top layer having a top surface and a bottom surface, the top layer being an n electrode; an uneven pattern formed in the bottom surface of the n electrode; an n-type semiconductor layer formed under the n electrode, the n-type semiconductor layer having a top surface and a bottom surface; an uneven pattern formed in the top surface of the n-type semiconductor layer, the uneven pattern of the n-type semiconductor layer corresponding to the uneven pattern of the n electrode; an active layer formed under the n-type semiconductor layer; a p-type semiconductor layer formed under the active layer; and a p electrode formed under the p-type semiconductor layer.
1. A semiconductor light emitting device, comprising:
a top layer having a top surface and a bottom surface, the top layer being an n electrode;
an uneven pattern formed in the bottom surface of the n electrode;
a GaN based n-type semiconductor layer formed under the n electrode, the GaN based n-type semiconductor layer having a top surface and a bottom surface;
an uneven pattern formed in the top surface of the GaN based n-type semiconductor layer, the uneven pattern of the GaN based n-type semiconductor layer directly physically contacting the uneven pattern of the n electrode;
an active layer formed under the GaN based n-type semiconductor layer;
a GaN based p-type semiconductor layer formed under the active layer; and
a p electrode formed under the GaN based p-type semiconductor layer,
wherein a light emitting structure including the GaN based n-type semiconductor layer, the active layer, and the GaN based p-type semiconductor layer generates light,
wherein a top surface of the light emitting structure directly contacts the n electrode,
wherein the GaN based n-type semiconductor layer only includes GaN based semiconductor materials,
wherein the uneven pattern formed in the top surface of the GaN based n-type semiconductor layer is directly formed in the GaN based n-type semiconductor layer,
wherein the uneven pattern formed in the top surface of the GaN based n-type semiconductor layer is formed at different intervals,
wherein at least the n electrode is formed over the entire top surface of the GaN based n-type semiconductor layer, or at least the p electrode is formed over the entire surface of the GaN based p-type semiconductor layer,
wherein an entire surface of the n electrode contacts the GaN based n-type semiconductor layer,wherein a width of the top surface of the top layer and a width of the bottom surface of the top layer are the same, and wherein a growing substrate is not disposed between the n electrode and the p electrode.
2. The semiconductor light emitting device of claim 1 , wherein the uneven pattern of the n electrode extends across an entire boundary between the n electrode and the GaN based n-type semiconductor layer.
3. The semiconductor light emitting device of claim 1 , wherein the GaN based p-type semiconductor layer is transparent.
4. The semiconductor light emitting device of claim 1 , wherein the active layer has a multi-quantum well structure.
5. The semiconductor light emitting device of claim 1 , further comprising a p-contact semiconductor layer between the GaN based p-type semiconductor layer and the p electrode.
6. The semiconductor light emitting device of claim 1 , further comprising an uneven pattern in the GaN based p-type semiconductor layer contacting the p electrode.
7. The semiconductor light emitting device of claim 6 , wherein the uneven pattern in the GaN based p-type semiconductor layer is periodic.
8. The semiconductor light emitting device of claim 6 , wherein the uneven pattern in the GaN based p-type semiconductor layer is non-periodic.