Photonic integrated circuit and package structure

1. A photonic integrated circuit having a central region and a peripheral region surrounding the central region, comprising:

a semiconductor layer;

a seal ring structure disposed on the semiconductor layer, wherein the seal ring structure is located in the peripheral region and has a plurality of recesses recessing towards the central region from a top view, the seal ring structure is a continuous structure from the top view, and the seal ring structure exhibits a comb shape from the top view; and

a plurality of silicon waveguides embedded in the semiconductor layer, wherein the semiconductor layer covers top surfaces of the plurality of the silicon waveguides.

2. The photonic integrated circuit of claim 1 , wherein at least a portion of each of the plurality of silicon waveguides is located within the recesses from the top view.

3. The photonic integrated circuit of claim 1 , wherein the plurality of silicon waveguides intersect a portion of the seal ring structure from the top view.

4. The photonic integrated circuit of claim 1 , wherein the seal ring structure is electrically floating.

5. The photonic integrated circuit of claim 1 , wherein an area enclosed by the seal ring structure is approximately 80% to approximately 99% of a total area of a top surface of the photonic integrated circuit.

6. The photonic integrated circuit of claim 1 , wherein the silicon waveguides are partially located within the recesses in a one-to-one manner from the top view.

7. A package structure, comprising:

an electric integrated circuit;

a photonic integrated circuit adjacent to the electric integrated circuit, wherein the photonic integrated circuit comprises a first seal ring structure and a plurality of silicon waveguides underneath the first seal ring structure, and the first seal ring structure comprises at least one recess from a top view;

a redistribution layer disposed on the electric integrated circuit and the photonic integrated circuit, wherein the redistribution layer comprises a second seal ring structure, and the second seal ring structure surrounds the first seal ring structure from the top view; and

a plurality of polymer waveguides disposed on the photonic integrated circuit and optically coupled to the plurality of silicon waveguides.

8. The package structure of claim 7 , wherein the first seal ring structure and the second seal ring structure are electrically floating.

9. The package structure of claim 7 , wherein the second seal ring structure extends along four edges of the package structure from the top view.

10. The package structure of claim 7 , wherein the plurality of polymeric waveguides are located within the at least one recess from the top view.

11. The package structure of claim 7 , wherein the at least one recess of the first seal ring structure comprises a plurality of recesses, and each of the plurality of recesses accommodates one of the plurality of polymer waveguides from the top view.

12. The package structure of claim 7 , wherein the second seal ring structure intersects the plurality of polymer waveguides from the top view.

13. The package structure of claim 7 , wherein each of the plurality of polymer waveguides overlaps with the corresponding silicon waveguide from the top view.

14. A package structure, comprising:

a photonic integrated circuit, wherein the photonic integrated circuit comprises a first seal ring structure and a plurality of silicon waveguides underneath the first seal ring structure, the first seal ring structure comprises a first segment, a second segment, a third segment, and a fourth segment, the second segment and the fourth segment connect the first segment and the third segment, the second segment is parallel to the fourth segment, the first segment comprises a first sub-segment, a second sub-segment, and a third sub-segment, the first sub-segment is connected to the second segment and the second sub-segment, the second sub-segment is connected to the first sub-segment and the third sub-segment, the first sub-segment and the third sub-segment are parallel to the third segment, and the second sub-segment is parallel to the second segment and the fourth segment;

a redistribution layer disposed on the photonic integrated circuit, wherein the redistribution layer comprises a second seal ring structure, and the second seal ring structure surrounds the photonic integrated circuit from a top view; and

a plurality of polymer waveguides disposed on the photonic integrated circuit and optically coupled to the plurality of silicon waveguides.

15. The package structure of claim 14 , wherein the second segment, the third segment, and the fourth segment respectively extend along three edges of the photonic integrated circuit.

16. The package structure of claim 14 , wherein the second sub-segment is perpendicular to the first sub-segment and the third sub-segment.

17. The package structure of claim 14 , wherein the first segment further comprises a fourth sub-segment and a fifth sub-segment, the fourth sub-segment is connected to the third sub-segment and the fifth sub-segment, the fifth sub-segment is connected to the fourth segment, the fourth sub-segment is parallel to the second sub-segment, and the fifth sub-segment is parallel to the first sub-segment and the third sub-segment.

18. The package structure of claim 14 , wherein the plurality of silicon waveguides are parallel to the second sub-segment.

19. The package structure of claim 14 , wherein the plurality of polymer waveguides are parallel to the second sub-segment.

20. The package structure of claim 14 , wherein the plurality of silicon waveguides are located underneath the third-sub segment of the first seal ring.