Imec demonstrates 896Gb/s silicon photonics transceiver

At this week’s OFC 2017, the largest global conference and exposition for optical communications, imec, the world-leading research and innovation hub in nano-electronics and digital technology, presents a 896Gb/s silicon photonics transceiver of just a few mm², targeting future Tb/s optical links. This 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. Silicon photonics (SiPh) has been identified as a promising technology platform to realize such aggressive bandwidth and integration targets, substantially going beyond 100Gb/s technology available today. 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 56Gb/s Germanium-Silicon (GeSi) electro-absorption modulators and GeSi waveguide photodetectors with a multi-core fiber interface. It comprises arrays of 16 GeSi electro-absorption modulators (EAM) and 16 GeSi photodetectors (PD), implemented with 100µm channel pitch on a single silicon chip. 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.

“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,” said 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.”

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 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 May 5, 2017.

PROFAs and full optoelectronic packaging services are available from Chiral Photonics (OFC Booth 3714).

Photograph of the PROFA attached to the GeSi SDM transceiver chip.

56Gb/s NRZ eye diagrams at 1565nm for the 16x GeSi EAM transmitter array.