Light-emitting device
View Patent ↗A light-emitting device includes a semiconductor light-emitting stack; a current injected portion formed on the semiconductor light-emitting stack; an extension portion having a first branch radiating from the current injected portion and having a first width, and a first length greater than the first width, and a second branch extending from the first branch and having a second width larger than the first width, and a second length greater than the second width; and an electrical contact structure between the second branch and the semiconductor light-emitting stack.
1. A light-emitting device comprising:
a semiconductor light-emitting stack;
a current injected portion formed on the semiconductor light-emitting stack;
an extension portion having a first branch radiating from the current injected portion and having a first width, and a first length greater than the first width, and a second branch extending from the first branch and having a second width larger than the first width, and a second length greater than the second width; and
an electrical contact structure between the second branch and the semiconductor light-emitting stack.
2. A light-emitting device of claim 1 , wherein the extension portion further comprises a third branch substantially parallel to the second branch.
3. A light-emitting device of claim 2 , wherein a length of the third branch is longer than that of the second branch.
4. A light-emitting device of claim 2 , wherein the second branch is closer to the current injected portion than the third branch is.
5. A light-emitting device of claim 1 , wherein the electrical contact structure comprises a third width smaller than the second width.
6. A light-emitting device of claim 1 , wherein the electrical contact structure and the second branch substantially have the same shape.
7. A light-emitting device of claim 1 , further comprising:
a substrate;
an adhesive layer; and
a reflective layer;
wherein the adhesive layer and the reflective layer are sandwiched by the semiconductor light-emitting stack and the substrate.
8. A light-emitting device of claim 1 , wherein the semiconductor light-emitting stack comprises a roughened surface.
9. A light-emitting device comprising:
a semiconductor light-emitting stack;
a current injected portion formed on the semiconductor light-emitting stack;
electrical contact structures being separated from the current injected portion, and comprising a first area and a second area separated from and larger than the first area; and
an extension portion being current-blocked with the semiconductor light-emitting stack except portions covering the electrical contact structures.
10. A light-emitting device of claim 9 , wherein the extension portion has a first branch radiating from the current injected portion, a second branch covering the first area, and a third branch covering the second area.
11. A light-emitting device of claim 10 , wherein the second branch is substantially parallel to the third branch.
12. A light-emitting device of claim 9 , wherein the second area is closer to the current injected portion than the first area is.
13. A light-emitting device of claim 9 , wherein electrical contact structures further comprises a third area separated from and larger than the first area.
14. A light-emitting device of claim 13 , wherein the extension portion has a forth branch covering the third area.
15. A light-emitting device of claim 13 , wherein the second area is between the first area and the third area.