Buried waveguide photodetector

A method of forming an integrated photonic semiconductor structure having a photodetector device and a CMOS device comprising:

• forming the CMOS device on a first silicon-on-insulator region;
• forming a silicon optical waveguide on a second silicon-on-insulator region;
• forming a shallow trench isolation region surrounding the silicon optical waveguide, the shallow trench isolation electrically isolating the first and the second silicon-on-insulator region;
• depositing, within a first region of the shallow trench isolation region, first germanium material adjacent a first side wall of the semiconductor optical waveguide;
• and
• depositing, within a second region of the shallow trench isolation region, second germanium material adjacent a second side wall of the semiconductor optical waveguide, the second side wall opposing the first side wall;
• wherein the deposited first and the deposited second germanium material form an active region of the photodetector device for evanescently receiving propagating optical signals from the first and the second side wall of the semiconductor optical waveguide.

An integrated photonic semiconductor structure comprising:

• a substrate;
• an isolation region;
• a CMOS device located on the substrate;
• a semiconductor optical waveguide structure located on the substrate and electrically isolated from the CMOS device by the isolation region, the semiconductor optical waveguide structure having a first side wall and a second side wall that opposes the first side wall;
• a photodetector located within the isolation region, the photodetector having a first and a second germanium active region, the first germanium active region located adjacent to the first side wall of the waveguide structure and the second germanium active region located adjacent to the second side wall of the waveguide structure,
• wherein the first and the second germanium active region evanescently receive propagating optical signals from the first and the second side wall of the semiconductor optical waveguide.

A design structure tangibly embodied in a machine readable medium for designing, manufacturing, or testing an integrated circuit, the design structure comprising:

• a substrate;
• an isolation region;
• a CMOS device located on the substrate;
• a semiconductor optical waveguide structure located on the substrate and electrically isolated from the CMOS device by the isolation region, the semiconductor optical waveguide structure having a first side wall and a second side wall that opposes the first side wall;
• a photodetector located within the isolation region, the photodetector having a first and a second germanium active region, the first germanium active region located adjacent to the first side wall of the waveguide structure and the second germanium active region located adjacent to the second side wall of the waveguide structure,
• wherein the first and the second germanium active region evanescently receive propagating optical signals from the first and the second side wall of the semiconductor optical waveguide.