Light-emitting device

1. A light-emitting device, comprising:

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

a via penetrating the active layer and the second semiconductor layer to expose the first semiconductor layer;

a first contact layer covering the via, electrically connected to the first semiconductor layer, and formed on the second semiconductor layer;

a second contact layer formed on the second semiconductor layer and electrically connected to the second semiconductor layer;

a first insulating layer comprising a first insulating layer first opening formed on the second semiconductor layer to expose the first contact layer;

a first pad on the semiconductor stack and covering the first insulating first opening; and

a second pad on the semiconductor stack and separated from the first pad with a distance to define a region between the first pad and the second pad on the semiconductor stack, wherein the first contact layer comprises a protrusion covering the via and the second contact layer comprises a recess surrounding the via.

2. The light-emitting device of claim 1 , wherein the second contact layer does not overlap the first contact layer in a top view of the light-emitting device.

3. The light-emitting device of claim 2 , wherein the first contact layer surrounds the second contact layer in the top view of the light-emitting device.

4. The light-emitting device of claim 1 , further comprising a second insulating layer comprising a second insulating layer first opening on the via to expose the first semiconductor layer and a second insulating layer second opening on the second semiconductor layer, wherein the second contact layer is formed in the second insulating layer second opening.

5. The light-emitting device of claim 1 , wherein the first insulating layer comprises a first insulating layer second opening to expose the second contact layer and the second pad covers the first insulating layer second opening.

6. The light-emitting device of claim 1 , wherein the first insulating layer first opening is offset from the via.

7. The light-emitting device of claim 1 , wherein the light-emitting device comprises a plurality of vias, the first contact layer comprises a plurality of first protrusions respectively covering the plurality of vias, and the second contact layer comprises a plurality of second recesses respectively surrounding the plurality of vias.

8. The light-emitting device of claim 1 , wherein the first contact layer comprises an area larger than an area of the second contact layer in a top view of the light-emitting device.

9. The light-emitting device of claim 1 , wherein the first pad and the second pad are formed in positions outside the via.

10. The light-emitting device of claim 1 , wherein the recess comprises a width larger than a diameter of the via.

11. The light-emitting device of claim 1 , further comprising a surrounding part surrounding the semiconductor stack and exposing the first semiconductor layer, wherein the first contact layer contacts the first semiconductor layer on the surrounding part.

12. A light-emitting device, comprising:

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

a plurality of vias penetrating the active layer and the second semiconductor layer to expose the first semiconductor layer;

a first contact layer covering the plurality of vias, electrically connected to the first semiconductor layer, and formed on the second semiconductor layer;

a first insulating layer comprising a first insulating layer first opening formed on the second semiconductor layer to expose the first contact layer;

a first pad on the semiconductor stack and covering the first insulating layer first opening; and

a second pad on the semiconductor stack and separated from the first pad with a distance to define a region between the first pad and the second pad on the semiconductor stack, wherein the first pad comprises a first pad opening corresponding to one of the plurality of vias and the second pad comprises a recess surrounding another one of the plurality of vias.

13. The light-emitting device of claim 12 , wherein the first insulating layer comprises a first insulating layer second opening on the second semiconductor layer and the second pad covers the first insulating layer second opening.

14. The light-emitting device of claim 12 , wherein the first insulating layer first opening is offset from the plurality of vias.

15. The light-emitting device of claim 12 , wherein the first pad and the second pad are formed in positions outside the plurality of vias.

16. The light-emitting device of claim 12 , wherein the first pad opening comprises a diameter larger than that of the one of the plurality of vias.

17. The light-emitting device of claim 12 , wherein the recess comprises a width larger than a diameter of the another one of the plurality of vias.

18. The light-emitting device of claim 12 , wherein first insulating layer comprises two or more sublayers having different refractive index alternately stacked to form a Distributed Bragg reflector (DBR).

19. The light-emitting device of claim 12 , further comprising a surrounding part surrounding the semiconductor stack and exposing the first semiconductor layer, wherein the first contact layer contacts the first semiconductor layer on the surrounding part.

20. The light-emitting device of claim 19 , wherein two adjacent vias of the plurality of vias located on a same row comprise a first shortest distance there between, any via of the plurality of vias adjacent to a first outside wall the first semiconductor layer on the surrounding part comprises a second shortest distance there between, and the first shortest distance is smaller than or equal to the second shortest distance.