Light-emitting device

1. A light-emitting device, comprising:

a semiconductor stack comprising a first semiconductor layer, an active layer and a second semiconductor layer;

an insulating reflective structure covering the semiconductor stack, comprising a first insulating reflective structure opening and a second insulating reflective structure opening;

a first contact electrode formed under the insulating reflective structure, and comprising a first bonding layer and a first conductive layer;

a first electrode pad formed on the first insulating reflective structure opening of the insulating reflective structure; and

a second electrode pad formed on the second insulating reflective structure opening of the insulating reflective structure,

wherein the first bonding layer comprises a first recess, and the first bonding layer comprises one part having a first thickness formed under the first recess and contacting the first conductive layer, and another part having a second thickness larger than the first thickness and surrounding the first recess and contacting the first conductive layer,

wherein the first recess comprises a first step difference smaller than a thickness of the insulating reflective structure, and

wherein the first insulating reflective structure opening comprises a first sidewall connected to the first bonding layer, and the first sidewall of the first insulating reflective structure opening and a sidewall of the first recess are separated with a minimum distance in a lateral direction perpendicular to the stacking direction of the semiconductor stack.

2. The light-emitting device according to claim 1 , wherein the first bonding layer comprises a bottom surface contacting the first conductive layer, and the bottom surface of the first bonding layer comprises an edge portion bent toward the first semiconductor layer.

3. The light-emitting device according to claim 1 , further comprising a substrate comprising a top surface and a dicing street surrounding the semiconductor stack, wherein the semiconductor stack and the dicing street are formed on the top surface of the substrate.

4. The light-emitting device according to claim 3 , wherein the dicing street comprises a width larger than 4 μm, but not more than 10 μm.

5. The light-emitting device according to claim 3 , wherein the substrate comprises a side surface connecting to the first side or the second side and comprising a lattice plane of M plane or A plane.

6. The light-emitting device according to claim 5 , wherein the light-emitting device comprises a third side connected to the first side and the second side, and a fourth side connected to the first side and the second side, and the dicing street comprises a first width on the first side or the second side which is larger than a second width on the third side or the fourth side.

7. The light-emitting device according to claim 3 , wherein the substrate comprises a side surface connecting to the first side or the second side and comprising a lattice plane of R plane.

8. The light-emitting device according to claim 7 , wherein the light-emitting device comprises a third side connected to the first side and the second side, and a fourth side connected to the first side and the second side, and the dicing street comprises a first width on the first side or the second side which is smaller than a second width on the third side or the fourth side.

9. The light-emitting device according to claim 1 , wherein any side of the light-emitting device is greater than 50 μm, but not more than 260 μm.

10. The light-emitting device according to claim 9 , wherein the light-emitting device comprises a longest side less than 200 μm, and a distance between the first electrode pad and the second electrode pad is larger than 10 μm but not more than 45 μm.

11. The light-emitting device according to claim 9 , wherein the light-emitting device comprises a longest side greater than 200 μm, and a distance between the first electrode pad and the second electrode pad is larger than 50 μm but not more than 150 μm.

12. The light-emitting device according to claim 1 , wherein the light-emitting device comprises a thickness between 50 μm and 110 μm.

13. The light-emitting device according to claim 12 , wherein the thickness is between 70 μm and 90 μm.

14. The light-emitting device according to claim 1 , wherein the insulating reflective structure comprises a protective layer covering the semiconductor stack, a reflective layer comprising a Distributed Bragg Reflector structure formed on the protective layer, and a cap layer covering the reflective layer.

15. The light-emitting device according to claim 1 , further comprising a substrate comprising a top surface, wherein the semiconductor stack is formed on the top surface of the substrate and the substrate further comprises one or a plurality of protrusions protruding from the top surface of the substrate, and the reflective layer comprises a fracture surface corresponding to a position adjacent to a connecting portion between an edge of the one or one of the plurality of protrusions and the top surface of the substrate.

16. The light-emitting device according to claim 15 , wherein the reflective layer comprises a surface topography corresponding to the plurality of the protrusions of the substrate.

17. The light-emitting device according to claim 1 , further comprising a second contact electrode formed under the second insulating reflective structure opening of the insulating reflective structure.

18. The light-emitting device according to claim 1 , further comprising a second contact electrode formed under the insulating reflective structure, and comprising a second bonding layer and a second conductive layer; wherein the second bonding layer comprises a second recess comprising a second step difference.

19. The light-emitting device according to claim 18 , wherein the first step difference or the second step difference is between 20 nm and 200 nm.

20. The light-emitting device according to claim 1 , wherein the minimum distance is between 5 nm and 100 nm.