Optical cladding layer design
Embodiments of the invention describe apparatuses, optical systems, and methods related to utilizing optical cladding layers. According to one embodiment, a hybrid optical device includes a silicon semiconductor layer and a III-V semiconductor layer having an overlapping region, wherein a majority of a field of an optical mode in the overlapping region is to be contained in the III-V semiconductor layer. A cladding region between the silicon semiconductor layer and the III-V semiconductor layer has a spatial property to substantially confine the optical mode to the III-V semiconductor layer and enable heat dissipation through the silicon semiconductor layer.
1. A semiconductor device comprising:
a cladding layer defining a longitudinal direction transverse to a surface of the cladding layer and a lateral direction parallel to the cladding layer;
a silicon semiconductor layer on another surface of the cladding layer opposite the surface of the cladding layer; and
a buried oxide layer on the silicon semiconductor layer, the buried oxide layer comprising a hole; and
a III-V semiconductor layer on the surface of the cladding layer, the III-V semiconductor layer having a wider lateral width that is wider than a narrow lateral width of the cladding layer, the III-V semiconductor layer having an active region with light confined in the III-V semiconductor layer by the narrow lateral width of the cladding layer.
2. The semiconductor device of claim 1 , wherein the light is of at least a first wavelength, and wherein the silicon semiconductor layer is shaped to form a waveguide for at least a first wavelength of light.
3. The semiconductor device of claim 2 , wherein the silicon semiconductor layer is shaped to form a shunt of silicon that extends into the cladding layer.
4. The semiconductor device of claim 3 , wherein the shunt has dimensions smaller than the first wavelength of light in the silicon semiconductor layer.
5. The semiconductor device of claim 3 , wherein the silicon semiconductor layer is shaped to form a plurality of additional thermal shunts that extend into the cladding layer.
6. The semiconductor device of claim 5 , wherein each of the plurality of additional thermal shunts has dimensions smaller than the first wavelength of light.
7. The semiconductor device of claim 1 , wherein the cladding layer comprises a dielectric material.
8. The semiconductor device of claim 7 , wherein the dielectric material has a thermal conductivity less than a thermal conductivity of silicon.
9. The semiconductor device of claim 1 , wherein at least a portion of the hole is longitudinally aligned with at least a portion of the narrow lateral width of the cladding layer.
10. The semiconductor device of claim 1 , wherein a thermally conductive material is in the hole, and wherein the thermally conductive material has a thermal conductivity greater than a thermal conductivity of the buried oxide layer.
11. The semiconductor device of claim 10 , wherein the thermally conductive material is one of: a polysilicon, metal, a thermal paste.
12. The semiconductor device of claim 10 , further comprising a substrate on the buried oxide layer, and wherein the hole extends through the substrate.
13. The semiconductor device of claim 12 , wherein the hole extends to the silicon semiconductor layer.
14. The semiconductor device of claim 13 , wherein the thermally conductive material in the hole extends to at least the silicon semiconductor layer.
15. The semiconductor device of claim 14 , wherein the hole extends through the silicon semiconductor layer to the cladding layer.
16. A method of manufacturing an optical device, the method comprising:
applying a cladding layer to an etched silicon semiconductor layer that is on a buried oxide layer that comprises a hole, the cladding layer having a surface with a longitudinal direction transverse to the surface and a lateral direction parallel to the cladding layer; and
applying a III-V semiconductor layer on the surface of the cladding layer, the III-V semiconductor layer having a wider lateral width that is wider than a narrow lateral width of the cladding layer, the III-V semiconductor layer having an active region with light confined in the III-V semiconductor layer by the narrow lateral width of the cladding layer.
17. The method of claim 16 , further comprising: etching silicon semiconductor material to form the etched silicon semiconductor layer.
18. The method of claim 16 , wherein the light is of at least a first wavelength, and wherein the etched silicon semiconductor layer is shaped to form a waveguide for at least a first wavelength of light.
19. The method of claim 18 , wherein the etched silicon semiconductor layer is shaped to form a shunt of silicon that extends into the cladding layer.
20. The method of claim 19 , wherein the shunt has dimensions smaller than the first wavelength of light in the etched silicon semiconductor layer.