Photonic package and method of manufacture
A package includes a laser diode includes a bonding layer; a first dielectric layer over the laser diode, wherein the first dielectric layer is directly bonded to the bonding layer of the laser diode; a first silicon nitride waveguide in the first dielectric layer, wherein the first silicon nitride waveguide extends over the laser diode; a second dielectric layer over the first silicon nitride waveguide; a silicon waveguide in the second dielectric layer; an interconnect structure over the silicon waveguide; and conductive features extending through the first dielectric layer and the second dielectric layer to electrically contact the interconnect structure.
1. A method comprising:
forming a first set of waveguides on a first side of a first dielectric layer, wherein the first set of waveguides comprises a photonic device;
forming a redistribution structure over the first set of waveguides, wherein the redistribution structure is electrically connected to the photonic device;
forming a second set of waveguides on a second side of the first dielectric layer, wherein the first set of waveguides and the second set of waveguides comprise different materials;
forming a second dielectric layer over the second set of waveguides;
bonding a laser substrate die to the second dielectric layer using a dielectric-to-dielectric bonding process; and
after the bonding the laser substrate die to the second dielectric layer, processing the laser substrate die to form a laser diode, wherein the laser diode is optically coupled to a waveguide of the second set of waveguides, wherein the processing the laser substrate die comprises at least one photolithographic masking and etching process.
2. The method of claim 1 , wherein the first set of waveguides comprises silicon and the second set of waveguides comprises silicon nitride.
3. The method of claim 1 , wherein the photonic device comprises a photodetector.
4. The method of claim 1 , wherein processing the laser substrate die comprises etching the laser substrate die.
5. The method of claim 1 , wherein the laser diode laterally overlaps the waveguide of the second set of waveguides.
6. The method of claim 1 further comprising:
forming a third dielectric layer over the laser diode; and
forming a plurality of first vias penetrating the third dielectric layer, wherein at least one first via electrically contacts the laser diode.
7. The method of claim 6 further comprising forming a plurality of second vias penetrating the second dielectric layer and the first dielectric layer, wherein at least one second via electrically contacts a first via and the redistribution structure.
8. The method of claim 1 , wherein the dielectric-to-dielectric bonding process comprises physically contacting an oxide layer of the laser substrate die to the second dielectric layer.
9. The method of claim 1 further comprising bonding a semiconductor die to the redistribution structure using fusion bonding, wherein the semiconductor die electrically contacts the redistribution structure.
10. A method comprising:
forming a silicon waveguide over a top surface of an oxide layer, wherein the oxide layer is over a top surface of a substrate;
forming a photonic device over the top surface of the oxide layer, wherein the photonic device is optically coupled to the silicon waveguide;
forming a redistribution structure over the silicon waveguide and the photonic device, wherein the redistribution structure is electrically connected to the photonic device;
bonding a semiconductor die to the redistribution structure, wherein the semiconductor die is electrically connected to the redistribution structure;
removing the substrate to expose a bottom surface of the oxide layer;
forming a first silicon nitride waveguide over the bottom surface of the oxide layer, wherein the first silicon nitride waveguide is optically coupled to the silicon waveguide;
forming a dielectric layer over the first silicon nitride waveguide and over the bottom surface of the oxide layer;
directly bonding a laser diode to the dielectric layer, wherein the laser diode is optically coupled to the first silicon nitride waveguide; and
forming vias over the bottom surface of the oxide layer, wherein the vias are electrically connected to the laser diode and the redistribution structure.
11. The method of claim 10 , wherein a portion of the first silicon nitride waveguide laterally overlaps a portion of the silicon waveguide.
12. The method of claim 10 further comprising forming a second silicon nitride waveguide over the first silicon nitride waveguide, wherein the dielectric layer is over the second silicon nitride waveguide, wherein the laser diode is optically coupled to the first silicon nitride waveguide through the second silicon nitride waveguide.
13. The method of claim 10 further comprising attaching a support structure to the semiconductor die.
14. The method of claim 10 further comprising forming a grating coupler over the top surface of the oxide layer, wherein the grating coupler is optically coupled to the silicon waveguide.
15. The method of claim 14 further comprising replacing a portion of the redistribution structure with a dielectric material, wherein the dielectric material extends over the grating coupler.
16. The method of claim 10 further comprising performing a planarization process on the dielectric layer before directly bonding the laser diode to the dielectric layer.
17. A method comprising:
forming a silicon waveguide in a first dielectric layer;
forming a silicon nitride waveguide in a second dielectric layer, wherein the second dielectric layer is on a first side of the first dielectric layer;
forming an interconnect structure over a second side of the first dielectric layer;
forming first conductive features extending through the first dielectric layer and the second dielectric layer to electrically contact the interconnect structure;
bonding a laser diode to the second dielectric layer, comprising directly bonding a bonding layer of the laser diode to the second dielectric layer, wherein the laser diode extends over the silicon nitride waveguide; and
after the bonding the laser diode, patterning the laser diode to expose conductive connectors of the laser diode.
18. The method of claim 17 further comprising bonding an electronic die to the interconnect structure.
19. The method of claim 17 further comprising forming a third dielectric layer over the laser diode.
20. The method of claim 19 further comprising forming second conductive features extending through the third dielectric layer to electrically contact the laser diode.