Integrated Photonics

Since nearly the advent of the semiconductor laser, there has been active research in the technology of integrating multiple device functionality onto a single device. Integration offers system advantages in terms of overall size, weight, and power as well as specific performance gains not necessarily available by combining multiple, bulk components. Many systems benefit from such enabling components including telecommunications, computational intra-chip or chip-to-chip high bandwidth communications, and RF analog information processing.

Sarnoff has developed semiconductor device technology to allow generation, modulation, routing, switching, and detection of light along with technology for all on-chip integration. This enables the processing of complex information on a platform inherently geared for wafer-scale fabrication. Capabilities used to develop such technology include advanced material/device design, expert material growth, standard and advanced fabrication processes such as high aspect ratio semiconductor etching, ultra-low-reflection facet coating, high speed contact processes, e-beam and high-resolution optical lithography.

Example technologies developed for active control and processing of optical information include multiple high-speed ring-resonator waveguides integrated onto a common waveguide bus, integratable linear phase modulators, ultra-low-jitter modelocked laser sources (utilized also as a source of multiple, coherent, optical tones of fixed frequency difference), and record-thin InP semiconductor membrane-waveguides for low-loss, tapped delay line, applications. Further, utilizing both the Sarnoff silicon and III-V fabrication facilities, a low-loss, post-processed amorphous silicon waveguide technology has been developed. This technology is specifically suited for low-cost, high yield, active/passive waveguide integration with an example platform device being the demonstration of an eight-channel laser on a single die.