Semiconductor light emitting device and fabrication method thereof
View Patent ↗The present invention relates to a semiconductor light emitting device comprising a sapphire substrate 11 ; a u-GaN layer 12 that is formed on top of the substrate 11 and that comprises a plurality of concave portions 121 formed into band-like shapes with predetermined intervals therebetween; a regrown u-GaN layer 13 formed on the u-Ga layer 12 ; a layered structure that is formed on the u-GaN layer 13 comprises an n-GaN layer 15 , an active layer 16 , and a p-GaN layer 19 ; an n-type electrode 24 formed on the n-GaN layer 15 exposed by removing a potion of the layered structure; and a transparent p-type electrode 20 formed on the p-GaN layer 19 , wherein the p-type electrode 20 is an emission detection surface, and an air layer S is formed between the bottom surface of the u-GaN layer 13 and the concave portions 121.
1. A semiconductor light emitting device comprising:
a first GaN based semiconductor layer that has on top thereof a plurality of concave portions formed into a band-like shape with predetermined intervals therebetween;
a second GaN based semiconductor layer formed on the first GaN based semiconductor layer;
a layered structure that is formed on the second GaN based semiconductor layer and that comprises an n-type GaN based semiconductor layer, an active layer, and a p-type GaN based semiconductor layer;
an n-type electrode that is formed on the n-type GaN based semiconductor layer on the portion where the layered structure is partially removed and become exposed; and
a transparent p-type electrode formed on the p-type GaN based semiconductor layer, wherein
the p-type electrode serves as an emission detection surface, and
an air layer is formed between the bottom surface of the second GaN based semiconductor layer and the concave portion.
2. A semiconductor light emitting device according to claim 1 , wherein the light emitted from the active layer reflects at the interface between the bottom surface of the second GaN based layer and the air layer.
3. A semiconductor light emitting device according to claim 1 , wherein
light-shielding regions to which wiring is applied are formed on the p-type electrode and n-type electrode; and
among the plurality of concave portions, the concave portions formed beneath the emission detection surface have a width greater than the concave portions formed beneath the light-shielding regions.
4. A semiconductor light emitting device according to claim 3 , wherein the width of the concave portions formed beneath the emission detection surface is at least twice that of the concave portions formed beneath the light-shielding regions.
5. A semiconductor light emitting device according to claim 4 , wherein the width of the concave portions formed beneath the emission detection surface is not less than 6 μm and not more than 20 μm.
6. A semiconductor light emitting device according to claim 4 , wherein the width of the concave portions formed beneath the light-shielding regions is not less than 1 μm and not more than 6 μm.
7. A semiconductor light emitting device according to claim 4 , wherein the width of the projecting portions formed between the concave portions that are formed beneath the light-shielding regions is not less than 1 μm and not more than 6 μm.
8. A semiconductor light emitting device according to claim 3 , wherein wire bonding is applied to the light-shielding regions.