With a goal of driving down the cost of high-speed optical interconnects and communications, the Intel photonics team is leveraging SOI to integrate multiple photonic components onto a single die.
In order to build smaller, faster, and less expensive optical components that fulfill the goal of universal, ubiquitous, low-cost, high-volume optical communications and interconnects, Intel is actively pursuing research work in silicon photonics. Read More
IBM researchers have made strategic advances in key elements needed to achieve on-chip optical networks.
The current trend in the microelectronics industry is to increase the parallelism in computation by multi-threading, by building large-scale multichip systems and, more recently, by increasing the number of cores on a single chip. With such an increase of parallelization the interconnect bandwidth between the racks, chips or different cores is becoming a limiting factor for the design of high performance computer systems. In particular, massively parallel processing within a multi-core architecture is becoming limited by large power consumption and limited throughput of global electrical interconnects.
To address this issue, the on-chip ultrahigh-bandwidth silicon-based photonic network might provide an attractive solution to this bandwidth bottleneck. Miniaturization of silicon photonic devices is a key towards practical realization of these ideas.
Silicon-on-insulator (SOI) technology is ideal for building ultra-dense photonic devices and circuits for an on-chip optical network.
Good optical isolation provided by the micron-thick buried oxide layer (BOX) allows one to shrink the core size of silicon waveguides to submicron cross-sections.
Simultaneously, owing to strong light confinement within a waveguide core, such waveguides, often called photonic wires, can route optical signals over very sharp corners with bending radii as small as just a few microns.
Recently IBM Research has demonstrated that this SOI-based technology opens the way to aggressively scale the footprint of all photonic components required for complex on-chip optical networks down to just a small fraction of a square millimeter. As it is typical in scaled CMOS devices, the power consumption of such devices is also dramatically reduced to sub-milliwatt levels.
Among recent IBM Research demonstrations are:
At this level of miniaturization the size of optical components is becoming comparable to the footprint of CMOS devices, suggesting the way towards monolithic integration of advanced CMOS circuits and nanophotonic optical components at the CMOS front-end.
Sony is investigating sculpting the waveguide between two layers of buried oxide.
The mainstream of microprocessor research activities has recently moved from increasing clock speed to multiplexing the number of microprocessors. Therefore, communication technology between microprocessors is of great interest in obtaining performance advantages. Read More
• Intel announced a hybrid silicon laser, which consists of an InP laser cavity that is directly bonded to a waveguide formed in an SOI substrate. Large numbers of such light emitters can be placed in one monolithic structure and provide very high bandwidth communication between microprocessor chips or even between individual cores.
Luxtera explains the role of SOI in its new technology.
Luxtera Inc., a fabless semicon-ductor company and the world leader in silicon photonics, announced recently that it has solved the longstanding problem of building advanced photonic interfaces into mass-produced silicon chips. For the first time, it is possible to integrate high-speed optical fiber interfaces in silicon devices produced in an industry- standard CMOS fabrication process. This capability will give computer and communication OEMs the performance benefits of optical-fiber communications, delivered with the economics of silicon. Read More
Intel has published two papers in Nature on silicon lasers. The first one (Nature, vol. 433, pp. 292 – 294, 20 January 2005) describes a pulsed laser; the second one (Nature, vol. 433, pp. 725 – 728, 17 February 2005) describes a continuous wave laser (an even bigger achievement). The text and figures in the actual Intel papers clearly indicate that SOI material was used in the development of the Intel silicon lasers.