Semiconductor light emitting device and method of fabricating thereof
A semiconductor light emitting device has a first conductive semiconductor layer, an active layer on the first conductive semiconductor layer and a second conductive semiconductor layer on the active layer. An oxide layer is disposed around the first semiconductor layer and is provided between the substrate and active layer. The first semiconductor layer has an uneven pattern along the side edge.
1. A semiconductor light emitting device comprising:
a substrate;
a first semiconductor layer on the substrate, wherein a side surface of a lateral periphery of the first semiconductor layer comprises a recessed portion;
an active layer on the first semiconductor layer;
a second conductive semiconductor layer on the active layer, wherein a portion of the recessed portion is recessed with respect to a side surface of a lateral periphery of the substrate and a side surface of a lateral periphery of the second conductive semiconductor layer; and
an oxide layer disposed on a side surface of the recessed portion around the first semiconductor layer,
wherein the oxide layer is provided between the substrate and the active layer,
wherein a portion of a top surface of the oxide layer is in contact with a bottom surface of the active layer,
wherein the oxide layer is on a top surface of the substrate, and
wherein the first semiconductor layer comprises a buffer layer and a first conductive semiconductor layer.
2. The semiconductor light emitting device of claim 1 , wherein a surface of the oxide layer comprises an uneven pattern, which is in contact with a side surface of the first semiconductor layer.
3. The semiconductor light emitting device of claim 1 , wherein the first semiconductor layer comprises an n-type semiconductor layer.
4. The semiconductor light emitting device of claim 2 , wherein the uneven pattern comprises at least one of a semi-circular form, a lens form, a curved form, a polygonal form, and a horn form.
5. The semiconductor light emitting device of claim 1 , wherein the oxide layer has an approximate thickness of 1 μm to 7 μm from a top surface of the substrate.
6. The semiconductor light emitting device of claim 2 , wherein an uneven pattern depth between a concave surface of the uneven pattern and a convex surface of the uneven pattern is in an approximate range between 1 μm and 50 μm.
7. The semiconductor light emitting device of claim 1 , wherein at least one of an electrode layer, a transparent electrode layer, an n-type semiconductor layer, and a reflective electrode layer is disposed on the second conductive semiconductor layer.
8. The semiconductor light emitting device of claim 2 , wherein the uneven pattern has a thickness approximately equal to the first semiconductor layer.
9. The semiconductor light emitting device of claim 2 , wherein the uneven pattern comprises a periodical pattern or a random pattern.