Method for producing an integrated optical circuit
A method for producing an integrated optical circuit comprising an active device and a passive waveguide circuit includes: applying an active waveguide structure on a source wafer substrate; exposing a portion of the source wafer substrate by selectively removing the active waveguide structure; applying a passive waveguide structure on the exposed portion of the source wafer substrate, wherein an aggregation of the active waveguide structure and the passive waveguide structure forms the active device, the active device having a bottom surface facing the source wafer substrate; removing the source wafer substrate from the active device; and attaching the active device to a target substrate comprising the passive waveguide circuit such that the bottom surface of the active device faces the target substrate.
1. A method for producing an integrated optical circuit comprising an active device and a passive waveguide circuit, the method comprising:
applying an active waveguide structure on a source wafer substrate;
exposing a portion of the source wafer substrate by selectively removing the active waveguide structure;
applying a passive waveguide structure on the exposed portion of the source wafer substrate, wherein an aggregation of the active waveguide structure and the passive waveguide structure forms the active device, the active device having a bottom surface facing the source wafer substrate;
removing the source wafer substrate from the active device; and
attaching the active device to a target substrate comprising the passive waveguide circuit such that the bottom surface of the active device faces the target substrate,
wherein applying the active waveguide structure on the source wafer substrate comprises growing a III-V thin-film on the source wafer substrate, and
wherein applying the passive waveguide structure on the exposed portion of the source wafer substrate comprises re-growing the III-V thin-film on the exposed portion of the source wafer substrate.
2. The method of claim 1 , comprising:
using an intermediate substrate to attach the active device to the target substrate.
3. The method of claim 1 , comprising:
using transfer printing to attach the active device to the target substrate.
4. The method of claim 1 ,
wherein the growing the III-V thin-film on the source wafer substrate comprises disposing a multiple quantum wells layer embedded in a doped layer structure over the source wafer substrate; and
wherein the re-growing the III-V thin-film on the exposed portion of the source wafer substrate comprises disposing a passive layer embedded in a non-doped layer structure over the exposed portion of the source wafer substrate.
5. The method of claim 1 , comprising:
disposing a common contact layer on a top surface of the applied active and passive waveguide structures before attaching the active device to the target substrate, the top surface of the applied active and passive waveguide structures being opposite to the bottom surface of the active device.
6. The method of claim 5 ,
wherein the common contact layer comprises bumps at a top surface of the active device making the top surface uneven, the top surface of the active device being opposite to the bottom surface of the active device.