This technology, dubbed CMOS Integrated Silicon Nanophotonics (I feel smarter already), integrates optical modules as well as electrical modules on a single piece of silicon. This allows electrical signals created at the transistor level to be transformed into light pulses, seemingly allowing chips to communicate faster according to IBM silicon photonics research scientist Will Green.
IBM believes that this new technology will lead to massive advances in supercomputer power. The fastest supercomputers we have around today max out at nearly 2 petaflops which, for us lay people, registers into two thousand trillion calculations per second. The photonics technology could increase this number to a staggering trillion million calculations per second. Yeah, a MILLION TRILLION calculations per second, otherwise known as an exaflop. This would help IBM achieve their goal of building an exascale computer by the year 2020.
According to Green, “In an exascale system, interconnects have to be able to push exabytes per second across the network. This is an interesting milestone for system builders who are looking at building exascale systems in 10 years.”
The possibility of integrating multiple photonics modules onto a single substrate or onto a motherboard is here, according to Green. Newer supercomputers already use optical technology for chips in order to communicate. However, this usually occurs at the rack level and mostly over a single wavelength. This breakthrough will allow optical communication simultaneously at multiple wavelengths.
The good thing about this technology is that it can be manufactured on a standard chip production line. Another benefit is that it also needs no special tools, making it extremely cost-effective. The current demonstration used a 130-nanometer CMOS manufacturing node. However, IBM plans on pursuing integration into “deeply scaled sub-100 nanometer CMOS processes,” according to Green.
The technology aims to replace copper wires. As you know, copper wires are widely used today for data transfer between chips. Optics can get a speed increase for distances as short as a few centimeters to as long as a few miles and even consumes less power. Eventually, IBM hopes to use optics for on-chip communication between transistors as well. According to Green, “There is a vision for the chip level, but that is not what we are claiming today.”