Semiconductor light emitting device having patterned substrate and manufacturing method of the same
View Patent ↗There is provided a semiconductor light emitting device having a patterned substrate and a manufacturing method of the same. The semiconductor light emitting device includes a substrate; a first conductivity type nitride semiconductor layer, an active layer and a second conductivity type nitride semiconductor layer sequentially formed on the substrate, wherein the substrate is provided on a surface thereof with a pattern having a plurality of convex portions, wherein out of the plurality of convex portions of the pattern, a distance between a first convex portion and an adjacent one of the convex portions is different from a distance between a second convex portion and an adjacent one of the convex portions.
1. A method of manufacturing a light emitting device including a substrate, a first conductivity type nitride semiconductor layer, an active layer and a second conductivity type nitride semiconductor layer, the method comprising:
forming a pattern having a plurality of convex portions on a surface of the substrate; and
growing the first conductivity type nitride semiconductor layer on the substrate where the pattern is formed,
wherein the forming a pattern on a surface of the substrate comprises forming the convex portions of the pattern such that a distance between a first convex portion and an adjacent one of the convex portions is different from a distance between a second convex portion and an adjacent one of the convex portions,
wherein the first conductivity type nitride semiconductor layer has a locally protruded and depressed structure and the active layer has a three-dimensional geometric curved indentation corresponding to the locally protruded and depressed structure of the first conductive nitride semiconductor layer.
2. The method of claim 1 , further comprising forming at least one buffer layer on the substrate, before the growing the first conductivity type nitride semiconductor layer.
3. The method of claim 1 , wherein the forming a pattern on a surface of the substrate comprises forming the first and second convex portions arranged non-periodically.
4. The method of claim 1 , wherein the forming a pattern on a surface of the substrate comprises forming the first and second convex portions each having a vertical cross-section formed of a hemisphere.
5. The method of claim 4 , wherein the forming a pattern on a surface of the substrate comprises forming the first and second convex portions having bottom surfaces sized differently from each other.
6. The method of claim 1 , wherein the forming a pattern on a surface of the substrate comprises the first and second convex portions each having a vertical cross-section formed of a polygon.
7. The method of claim 6 , wherein the forming a pattern on a surface of the substrate comprises forming the first and second convex portions having bottom surfaces sized differently from each other.
8. The method of claim 6 , wherein the forming a pattern on a surface of the substrate comprises forming the first and second convex portions differing in a growth plane of a nitride semiconductor from each other.
9. The method of claim 1 , wherein the forming a pattern on a surface of the substrate comprises forming the first and second convex portions having vertical cross-sections formed of a combination of a hemisphere and a polygon.
10. The method of claim 6 , wherein the polygon comprises one of a trapezium, a square and a triangle.
11. The method of claim 9 , wherein the polygon comprises one of trapezium, a square and a triangle.
12. The method of claim 1 , wherein the forming a pattern on a surface of the substrate comprises forming the convex portions each having a size of 0.1 μm to 10 μm.
13. The method of claim 1 , wherein the substrate is a sapphire substrate.