Light-emitting device having patterned substrate and method of manufacturing thereof
View Patent ↗A light-emitting device disclosed herein comprises a patterned substrate having a plurality of cones, wherein a space is between two adjacent cones. A light-emitting stack formed on the cones. Furthermore, the cones comprise an area ratio of a top area of the cone and a bottom area of the cone which is less than 0.0064.
1. A light-emitting device, comprising:
a patterned substrate having a plurality of cones, wherein each of the plurality of cones comprises a top having a top width, a bottom having a bottom width, a sidewall between the top and the bottom, and a height H, wherein an area ratio of the top and the bottom of the cone is less than 0.0064 and H>1.5 μm; and a light-emitting stack formed on the cones, wherein the light-emitting stack comprises a first conductivity-type semiconductor layer, an active layer, and a second conductivity-type semiconductor layer.
2. The light-emitting device according to claim 1 , wherein the sidewall between the top and the bottom is inclined.
3. The light-emitting device according to claim 1 , wherein the shape of the top comprises a circle.
4. The light-emitting device according to claim 1 , wherein the shape of the bottom comprises a circle.
5. The light-emitting device according to claim 2 , wherein a cross-section of the inclined sidewall comprises an arc with a chord protruded outward.
6. The light-emitting device according to claim 1 , further comprising an intermediate layer having a refractive index formed on the patterned substrate.
7. The light-emitting device according to claim 6 , wherein the top width is smaller than the quotient of the wavelength of light emitted from the light-emitting device divided by the refractive index of the intermediate layer.
8. The light-emitting device according to claim 1 , wherein the top width of the cone is smaller than 0.1 μm.
9. The light-emitting device according to claim 5 , further comprising a distance between two of the adjacent cones, wherein the distance is between 0.1-0.4 μm.
10. The light-emitting device according to claim 2 , wherein an angle between the bottom of the cone and the chord of the arc is between 40-60 degrees.
11. The light-emitting device according to claim 9 , wherein a maximum distance between the arc and the chord of the arc is smaller than 0.5 μm.
12. The light-emitting device according to claim 1 , wherein a first ratio of the top width of the cone to the bottom width of the cone is smaller than 0.08.
13. The light-emitting device according to claim 1 , wherein at least one of the cones satisfies 0.4<H/(D 1 +S)<=0.6, wherein D 1 represents the bottom width of the cone, and S represents the distance between two of the adjacent cones.
14. The light-emitting device according to claim 9 , wherein at least one of the cones satisfies 0.01<S/(D 1 +S)<0.3, wherein D 1 represents the top width of the cone, and S represents the distance between two of the adjacent cones.
15. The light-emitting device according to claim 11 , wherein at least one of the cones satisfies 0<B/(D I+S)<=0.2, wherein D 1 represents the top width of the cone, B represents the maximum distance of the arc and the chord of the arc, and S represents the distance between two of the adjacent cones.
16. The light-emitting device according to claim 1 , wherein the area of the top of the cone is zero.