Fabrication method for photonic devices

1. A method for constructing a device, the method comprising:

receiving a first wafer comprising a first layer stack, wherein the first layer stack comprises:

a substrate layer;

a seed layer disposed on the substrate layer; and

an electro-optic layer disposed on the seed layer;

etching the electro-optic layer to produce a ridge waveguide structure with a first thickness disposed between first and second slab layers of the electro-optic layer with a second thickness smaller than the first thickness;

receiving a second wafer; and

after etching the electro-optic layer:

bonding the first layer stack to the second wafer;

removing the substrate layer;

etching the seed layer to form, in the seed layer, a first electrode separated from a second electrode; and

depositing a second cladding layer on the first electrode and the second electrode.

2. The method of claim 1 , further comprising:

depositing a first cladding layer on the electro-optic layer after etching the electro-optic layer,

wherein bonding the first layer stack to the second wafer comprises bonding a surface of the first cladding layer to the second wafer.

3. The method of claim 2 , further comprising:

prior to bonding the surface of the first cladding layer to the second wafer, planarizing the first cladding layer.

4. The method of claim 1 , the method further comprising:

etching the second cladding layer to expose a first portion of the first electrode;

etching the second cladding layer to expose a second portion of the second electrode;

depositing a first lead onto the first electrode through the exposed first portion; and

depositing a second lead onto the second electrode through the exposed second portion.

5. The method of claim 1 ,

wherein the first thickness is between 200 and 350 nanometers (nm), and

wherein the second thickness is less than 150 nm.

6. The method of claim 5 ,

wherein the substrate layer comprises a silicon-on-insulator (SOI) wafer, and

wherein a silicon layer of the SOI wafer is in contact with the seed layer.

7. The method of claim 1 ,

wherein the second wafer comprises an optical interposer.

8. The method of claim 1 ,

wherein seed layer is composed of one of:

strontium titanate;

barium strontium titanate;

hafnium oxide;

zirconium oxide;

titanium oxide;

graphene oxide;

tantalum oxide;

lead zirconium titanate;

lead lanthanum zirconium titanate;

magnesium oxide;

germanium; or

strontium barium niobate, and

wherein the electro-optic layer is composed of one of:

barium titanate;

barium strontium titanate;

lithium niobite;

lead zirconium titanate;

lead lanthanum zirconium titanate;

aluminum oxide;

aluminum nitrite; or

strontium barium niobate.

9. A method for constructing a device, the method comprising:

receiving a first wafer comprising a first layer stack, wherein the first layer stack comprises:

a seed layer disposed on a substrate layer;

an electro-optic layer disposed on the seed layer; and

an electrode layer disposed on the electro-optic layer;

etching the electrode layer to expose a portion of the electro-optic layer and split the electrode layer into a first electrode separated from a second electrode;

depositing a first cladding layer on the exposed portion of the electro-optic layer and the first and second electrodes;

bonding a surface of the first cladding layer to a second wafer;

removing the substrate layer and the seed layer;

after removing the substrate layer and the seed layer, etching the electro-optic layer to produce a ridge waveguide with a first thickness disposed between first and second slab layers with a second thickness smaller than the first thickness; and

depositing a second cladding layer on the first and second slab layers and the ridge waveguide structure.

10. The method of claim 9 , the method further comprising:

prior to bonding the first cladding layer to the second wafer, planarizing the first cladding layer.

11. The method of claim 9 , the method further comprising:

etching through the second cladding layer and the first slab layer to expose a first portion of the first electrode;

etching through the second cladding layer and the second slab layer to expose a second portion of the second electrode;

depositing a first lead onto the first electrode through the exposed first portion; and

depositing a second lead onto the second electrode through the exposed second portion.

12. The method of claim 9 , further comprising:

wherein the substrate layer comprises a silicon-on-insulator (SOI) wafer, and

wherein a silicon layer of the SOI wafer is in contact with the seed layer.

13. The method of claim 9 ,

wherein the second wafer comprises an optical interposer.

14. The method of claim 9 ,

wherein seed layer is composed of one of:

strontium titanate;

barium strontium titanate;

hafnium oxide;

zirconium oxide;

titanium oxide;

graphene oxide;

tantalum oxide;

lead zirconium titanate;

lead lanthanum zirconium titanate;

magnesium oxide;

germanium; or

strontium barium niobate, and

wherein the electro-optic layer is composed of one of:

barium titanate;

barium strontium titanate;

lithium niobite;

lead zirconium titanate;

lead lanthanum zirconium titanate;

aluminum oxide;

aluminum nitrite; or

strontium barium niobate.

15. A method for constructing a device, the method comprising:

receiving a first wafer comprising a first layer stack, wherein the first layer stack comprises:

a seed layer disposed on a substrate layer;

an electro-optic layer disposed on the seed layer; and

a first cladding layer disposed on the electro-optic layer;

bonding the first cladding layer to a second wafer;

removing the substrate layer and the seed layer;

after removing the substrate layer and the seed layer, etching the electro-optic layer to produce a ridge waveguide with a first thickness disposed between a first slab layer and a second slab layer, wherein the first and second slab layers have a second thickness smaller than the first thickness;

depositing a first and second electrode on left and right sides, respectively, of the ridge waveguide structure; and

depositing a second cladding layer on the first and second electrodes and the ridge waveguide structure.

16. The method of claim 15 , the method further comprising:

prior to bonding the first cladding layer to the second wafer, planarizing the first cladding layer.

17. The method of claim 16 ,

wherein seed layer is composed of one of:

strontium titanate;

barium strontium titanate;

hafnium oxide;

zirconium oxide;

titanium oxide;

graphene oxide;

tantalum oxide;

lead zirconium titanate;

lead lanthanum zirconium titanate;

magnesium oxide;

germanium; or

strontium barium niobate, and

wherein the electro-optic layer is composed of one of:

barium titanate;

barium strontium titanate;

lithium niobite;

lead zirconium titanate;

lead lanthanum zirconium titanate;

aluminum oxide;

aluminum nitrite; or

strontium barium niobate.

18. The method of claim 15 , the method further comprising:

etching through the second cladding layer to expose a first portion of the first electrode;

etching through the second cladding layer to expose a second portion of the second electrode;

depositing a first lead onto the first electrode through the exposed first portion; and

depositing a second lead onto the second electrode through the exposed second portion.

19. The method of claim 15 ,

wherein the substrate layer comprises a silicon-on-insulator (SOI) wafer, the method further comprising:

oxidizing a top silicon layer of the SOI wafer in contact with the seed layer.

20. The method of claim 15 ,

wherein the second wafer comprises an optical interposer.