This Small Business Innovation Research Phase I project advances the field of silicon photonics which is emerging as a new, low cost, low power interconnect technology in applications as diverse as Active Cables for High Performance Computing to 100 Gb/s Ethernet transceivers for network centers. Like any new technology, silicon photonics has significant challenges incorporating disparate functions. To date the performance and size of optical building blocks are compromised by the wafer selection and the fabrication process. Some building blocks, wavelength multiplexers, for example, are best designed with waveguides in the 3-4 microns range for low loss and easy coupling to the outside world. Other building blocks, modulators for example, require waveguides of a single micron to keep their size small. The objective of this project is to address this integration challenge and demonstrate full feasibility for monolithic integration of optical components requiring vastly different geometrical and dimensional needs for light management on the same silicon wafer. In particular, modulators and multiplexers will be integrated onto the same chip.
The broader impact / commercial potential of this project can be similar to the revolution witnessed in the semiconductor industry in the past few decades. Here innovation has enabled the semiconductor industry to grow to more than $250B in yearly sales. This has fueled dozens more businesses in high technology, software, communications, entertainment and health industries creating millions of jobs and a huge portion of the wealth in the U.S. and around the world. Silicon photonics brings a new level of innovation to semiconductor industry by incorporating optics onto the chip itself. There are two key problems with electrical paths: they are power hungry; and, only one lane wide. By contrast, optical signals can be separated into colors or wavelengths with each wavelength carrying its own signal on a waveguide re-used by many other optical signals. Muliplexers (WDM) are used to separate and combine wavelengths; modulators are used to encode the signals. Geo-photonics will take silicon photonics to a new level. This technology platform will replace electrical interconnect with optical ones in the next generation of Ethernet computers, network centers, storage and video servers, terabit routers, and supercomputers. It will ensure U.S. leadership in this new category of semiconductors.
