Optical redistribution layers for high-channel-count photonics

A method for manufacturing an optical transceiver comprising transmitter circuitry and loopback circuitry, the method comprising:

• patterning a silicon layer of a silicon-on-insulator substrate to form the loopback circuitry therein;
• bonding a silicon substrate coated with a dielectric layer with the dielectric layer down onto the patterned silicon layer;
• breaking the silicon substrate along a layer of implanted defects to create a second silicon layer on top of the dielectric layer;
• patterning the second silicon layer to form passive device structures of the transmitter circuitry;
• and
• bonding one or more III-V die to the patterned second silicon layer and patterning the bonded III-V to form active device structures of the transmitter circuitry.

A photonic integrated circuit (PIC) comprising:

• a device layer comprising a first silicon waveguide layer;
• a second silicon waveguide layer separated from the first silicon waveguide layer by a dielectric layer;
• formed in the device layer, optical transmitter circuitry comprising four lasers configured to emit light at four respective wavelengths, the optical transmitter circuitry configured to split light from each of the four lasers between four lanes to create sixteen lanes, optically modulate the light in each of the sixteen lanes to generate a modulated optical signal associated with the respective lane, and multiplex the modulated optical signals across the four wavelengths to generate four optical transmitter output signals;
• and,
• formed in the second silicon waveguide layer, optical loopback circuitry optically coupled to the optical transmitter circuitry and configured to selectively couple the modulated optical signal associated with each lane to a photodiode associated with the lane.