Optoelectronic device
An optoelectronic device, including: a rib waveguide, the rib waveguide including: a ridge portion, which includes a temperature-sensitive optically active region, and a slab portion, positioned adjacent to the ridge portion; the device further comprising a heater, disposed on top of the slab portion wherein a part of the heater closest to ridge portion is at least 2 μm away from the ridge portion. The device may also have a heater provided with a bottom cladding layer, and may also include various thermal insulation enhancing cavities.
1. An optoelectronic device, including:
a rib waveguide, the rib waveguide including:
a ridge portion, which includes a temperature-sensitive optically active region, and
a slab portion, positioned adjacent to the ridge portion;
a heater, disposed on top of the slab portion wherein a part of the heater closest to the ridge portion is at least 2 μm away from the ridge portion;
a bottom cladding layer, disposed adjacent to the slab portion; and
a thermal isolation trench, wherein the thermal isolation trench is positioned adjacent to the bottom cladding layer,
wherein the thermal isolation trench is filled with air, or silicon dioxide, or air and silicon dioxide, and
wherein the thermal isolation trench is at least partially filled with air.
2. The optoelectronic device of claim 1 , wherein a width of a first region of the heater tapers from a first width to a second width in a direction substantially parallel to a guiding direction of the rib waveguide.
3. The optoelectronic device of claim 2 , wherein a width of a second region of the heater increases from the second width to the first width along the direction substantially parallel to the guiding direction of the rib waveguide.
4. The optoelectronic device of claim 1 , wherein the heater comprises plural metal strips, connected at one end to an adjacent metal strip so as to form a serpentine form.
5. The optoelectronic device of claim 4 , wherein the heater comprises at least 2 metal strips and no more than 20 metal strips.
6. The optoelectronic device of claim 4 , further including a first and second electrode for the heater, which are electrically connected to the heater on the same side.
7. The optoelectronic device of claim 4 , wherein each metal strip has a width of at least 0.5 μm and no more than 10 μm.
8. The optoelectronic device of claim 4 , wherein a gap between adjacent metal strips has a width of at least 0.5 μm and no more than 10 μm.
9. The optoelectronic device of claim 4 , wherein the heater is formed from a material selected from the group consisting of Ti, TiN, TiW, NiCr, and W.
10. The optoelectronic device of claim 1 , wherein the heater is disposed above an electrical contact for the slab portion and separated therefrom by an insulator.
11. The optoelectronic device of claim 1 , further including an upper cladding layer disposed on the heater.
12. The optoelectronic device of claim 1 , wherein the heater is a first heater, the optoelectronic device further including a second heater, substantially identical to the first heater and disposed on an opposing side of the ridge portion.
13. The optoelectronic device of claim 1 , wherein the thermal isolation trench has a width of at least 0.5 μm and no more than 2.0 μm.
14. The optoelectronic device of claim 1 , wherein the optoelectronic device includes plural thermal isolation trenches, which are arranged around a periphery of the slab portion.
15. The optoelectronic device of claim 1 , wherein the optoelectronic device further includes:
a thermal isolation cavity, located on an opposing side of the bottom cladding layer to the slab portion.
16. The optoelectronic device of claim 15 , further including:
a buried oxide layer, disposed adjacent to a lower surface of the bottom cladding layer, wherein the thermal isolation cavity is located on an opposing side of the buried oxide layer and is adjacent to a silicon substrate.
17. The optoelectronic device of claim 15 , wherein the thermal isolation cavity has a width which is larger than a width of the slab portion.
18. The optoelectronic device of claim 1 , further comprising an electrode, electrically connected to either the ridge portion or the slab portion, wherein the electrode includes at least one thermal isolation cavity.
19. The optoelectronic device of claim 18 , wherein the electrode comprises plural thermal isolation cavities in an array, wherein the array extends in a direction substantially parallel to a guiding direction of the rib waveguide.
20. The optoelectronic device of claim 19 , wherein the array extends for a length of at least 50 μm and no more than 100 μm.
21. The optoelectronic device of claim 19 , wherein a gap between adjacent cavities in the electrode has a length of at least 1 μm and no more than 20 μm.
22. The optoelectronic device of claim 18 , wherein the electrode comprises at least 2 cavities and no more than 30 cavities.
23. The optoelectronic device of claim 18 , wherein the thermal isolation cavity or each thermal isolation cavity in the electrode has a length of at least 2 μm and no more than 30 μm.
24. The optoelectronic device of claim 18 , wherein the thermal isolation cavity or each thermal isolation cavity in the electrode has a width of at least 1 μm and no more than 10 μm.
25. The optoelectronic device of claim 18 , wherein the thermal isolation cavity or each thermal isolation cavity in the electrode is filled with air or SiO 2 .
26. The optoelectronic device of claim 1 ,
wherein the bottom cladding layer is disposed below the slab portion, and
wherein the thermal isolation trench is positioned below the slab portion.