Optical chip, optical chip fabrication method, optical signal transmission method, and optical module

An optical chip fabrication method, comprising:

• providing a silicon-on-insulator (SOI) substrate, wherein the SOI substrate comprises a silicon substrate and an oxide layer;
• disposing an optical port, a polarization splitter and rotator (PSR), and at least one wavelength demultiplexer (DeMux) in the oxide layer;
• and
• fabricating a photodetector array on the silicon substrate, wherein the optical port, the PSR, and the at least one DeMux are made of silicon nitride (SiN), wherein
• the optical port is coupled to a fiber, and is configured to receive a first optical signal from the fiber, wherein the first optical signal comprises a component in a transverse magnetic TM mode;
• the PSR is configured to perform first processing on the first optical signal to generate a second optical signal, wherein the second optical signal is in a transverse electric TE mode, and the second optical signal is a single-channel multi-wavelength optical signal;
• the at least one DeMux is configured to perform second processing on the second optical signal to generate a third optical signal, wherein the third optical signal is a multi-channel single-wavelength optical signal;
• and
• the photodetector array is configured to convert the third optical signal into an electrical signal.

An optical module, comprising a housing, wherein

• a substrate;
• an electrical chip, configured to generate a radio frequency signal or process a radio frequency signal, and located on the substrate;
• an optical chip, located on the substrate;
• and
• a signal line, located on the substrate, and configured to transmit the radio frequency signal between the electrical chip and the optical chip, wherein the optical chip, comprising:
• an optical port, coupled to a fiber and configured to receive a first optical signal from the fiber, wherein the first optical signal comprises a component in a transverse magnetic (TM) mode;
• a polarization splitter and rotator (PSR), configured to perform first processing on the first optical signal to generate a second optical signal, wherein the second optical signal is in a transverse electric (TE) mode, and the second optical signal is a single-channel multi-wavelength optical signal;
• at least one wavelength demultiplexer (DeMux), configured to perform second processing on the second optical signal to generate a third optical signal, wherein the third optical signal is a multi-channel single-wavelength optical signal;
• and
• a photodetector array, configured to convert the third optical signal into an electrical signal, wherein
• the optical port, the PSR, and the at least one DeMux are made of silicon nitride (SiN).