Optoelectronic emitter having a phase-controlled antenna array comprising optical antennas suitable for emitting light radiation according to a predefined emission profile and in a predefined direction

A process for fabricating an optical phased array transmitter including a splitter coupled to a laser source;

• a plurality of waveguides, coupled to the splitter and extending along a longitudinal axis in a main plane, forming arms of the optoelectronic transmitter a plurality of phase shifters and optical antennas, arranged in the arms, each optical antenna being formed by the corresponding waveguide and by a diffraction grating located above and at a distance from the waveguide along a vertical axis orthogonal to the main plane, the process comprising:
• defining a target near-field emission profile and a target emission angle for light radiation emitted by each optical antenna, and a structural configuration of said optical antennas, comprising:
• values of physical parameters of the waveguides defining optical properties of transmission of an optical mode from the laser source, and values of physical parameters of the diffraction gratings defining optical properties of diffraction of the optical mode;
• determining a first relationship expressing a change in a pitch of periodic structures of the diffraction grating as a function of a width of the waveguide, such that, taking into account said structural configuration an emission angle of the light radiation emitted by the optical antenna is equal to said target emission angle;
• determining a second relationship expressing a change in an extraction rate of the diffraction grating as a function of the width of the waveguide, taking into account said first relationship and said structural configuration;
• determining a longitudinal variation wc(x) in the width of the waveguide and deducing a corresponding longitudinal variation in the pitch of the diffraction grating based on said first relationship, such that, taking into account said relationship and said structural configuration field emission profile of the light radiation emitted by the optical antenna is equal to said target emission profile;
• and
• fabricating the optoelectronic transmitter whose optical antennas have the reference structural configuration, supplemented by said longitudinal variation in the width of the waveguide and said longitudinal variation in the pitch of the diffraction grating.