Imec demonstrates 896Gb/s silicon photonics transceiver

At the Optical Fiber Communication Conference & Exhibition (OFC 2017) in Los Angeles (21-23 March), nanoelectronics research centre imec of Leuven, Belgium is presenting a 896Gb/s silicon photonics transceiver of just a few mm2, targeting future Tb/s optical links. The achievement highlights the scalability of imec’s iSiPP50G silicon photonics platform, paving the way for next-generation short-reach optical interconnects.

Driven by exponential demand for interconnect bandwidth in datacenters, single-mode optical transceivers will need to scale to Tb/s capacity and be tightly integrated with network switches, says imec. Silicon photonics (SiPh) has been identified as a promising technology platform for realizing such aggressive bandwidth and integration targets, substantially going beyond the 100Gb/s technology available currently. In the work presented at OFC, imec combines recently developed 50GHz active optical components with a multi-core fiber interface to showcase a proof-of-concept 896Gb/s spatial-division multiplexing SiPh transceiver.

The bi-directional 896Gb/s silicon photonics transceiver combines dense arrays of 16 56Gb/s germanium-silicon (GeSi) electro-absorption modulators (EAMs) and 16 GeSi waveguide photodetectors (PD) – implemented with 100µm channel pitch on a single silicon chip – together with a multi-core fiber interface. Both the EAM and PD devices are realized in a single GeSi epitaxial growth step, allowing a simple fabrication scheme. The chip co-integrates optical power splitters to feed a single laser source to the transmitter channels, and a dense array of fiber grating couplers to interface with a pitch-reducing optical fiber array (PROFA), provided and packaged by Chiral Photonics Inc of Pine Brook, NJ, USA

“We obtained clear and wide-open eye diagrams at 56Gb/s non-return-to-zero on-off keying (NRZ-OOK) data rate, for all EAM and PD channels tested in a loop-back transmission experiment,” says Joris Van Campenhout, director of the Optical I/O R&D program at imec. “These results clearly show the potential to realize ultra-compact multi-channel optical transceivers in imec’s 50G silicon photonics platform, targeting future Tb/s-scale interconnects,” he adds.

The GeSi EAM and PD components are available for evaluation by companies and academia through imec’s silicon photonics prototyping service and the iSiPP50G multi-project wafer (MPW) service provided by Europractice. The iSiPP50G platform includes a validated passive and active device library and is supported by photonic design software solutions from multiple electronic design automation (EDA) vendors, including Synopsys, Luceda Photonics and Lumerical, in current or upcoming releases.

The Europractice MPW services target datacom, telecom and sensing industries, photonic ASIC ecosystems and academia in the mentioned fields. In 2017, new MPW runs are available at four fixed tape-in dates. First closing date for registering to iSiPP50G technologies is 5 May.

PROFAs and full optoelectronic packaging services are available from Chiral Photonics (exhibiting in booth 3714 at OFC).