Semiconductor opto-electronic integrated circuits and methods of forming the same

A method of forming a semiconductor opto-electronic integrated circuit, the method comprising:

• forming an optical waveguide on a substrate, the optical waveguide having an optical grating, the optical waveguide extending along a first direction and having an input terminal and an output terminal, the optical waveguide providing an optical path along the first direction for optical signals traveling from the input terminal;
• providing a cladding layer between the optical waveguide and the substrate, the cladding layer being configured to contain the optical signals traveling between the input terminal and the output terminal within the optical waveguide;
• providing an optical active device on the optical grating, the optical active device having an optical active layer provided between first and second reflective layers, the first reflective layer being disposed on the optical grating and having a lower reflectivity than the second reflective layer.
• wherein the first reflective layer is configured to allow a selected optical signal to pass through the first reflective layer and into the optical active layer according to a control signal received by the optical active device,
• wherein the optical active layer is configured to modulate the selected optical signal that has passed through the first reflective layer, and
• wherein the second reflective layer is configured to reflect the optical signal modulated by the optical active layer to the optical waveguide and be transmitted to the output terminal of the optical waveguide.