“Nvidia Explores Silicon Photonics for Datacentre AI Efficiency”

Nvidia has collaborated with foundry TSMC to develop high-speed optical interconnect technology aimed at reducing power consumption in AI data centers equipped with millions of GPUs. According to Nvidia CEO Jensen Huang, the company is introducing its first co-packaged optics (CPO) silicon photonics system boasting 1.6Tbit/s performance based on micro ring resonator technology developed at TSMC.

Huang emphasized the significance of this technology, stating, "We use this to go from the GPU to the switch to the next switch. Each one of these connects 100,000 GPUs with another 100,000, and so on, so every GPU will have six transceivers, adding 180W per GPU. So how do we scale up to millions of GPUs? That’s 6m transceivers with 180MW of power."

The initial iteration of this technology is set to be utilized later this year for a MultiRing Module (MRM), which will then be integrated into the Spectrum-X switch in the latter half of 2026. This integration will enable direct fiber connection into the switches with 512 ports of 800Gbit/s, paving the way for scaling up to multi-million GPUs.

Notably, this advancement is based on the 6nm COUPE N6 process technology at TSMC, featuring 3D CoWoS packaging. The design will be made available for licensing to partners, including prominent industry players such as TSMC, Browave, Coherent, Corning, Fabrinet, Foxconn, Lumentum, SENKO, SPIL, Sumitomo Electric Industries, and TFC Communication.

In addition to these collaborations, Nvidia has also worked closely with Broadcom on the technology, further enhancing energy efficiency to accommodate more racks of the next-generation Rubin GPUs. Huang highlighted the potential energy savings, stating, "We could save 10s of megawatts. 6MW is 10 Rubin Ultra racks – 60MW is 100 Rubin Ultra racks."

Chairman and CEO of TSMC, C. C. Wei, expressed optimism about the future of AI data centers, emphasizing the importance of energy efficiency and scalability. He stated, "TSMC’s silicon photonics solution combines our strengths in both chip manufacturing and TSMC-SoIC 3D chip stacking to help NVIDIA unlock an AI factory’s ability to scale to a million GPUs and beyond, pushing the boundaries of AI."

Furthermore, Pierre Barnabé, CEO of French optical materials supplier Soitec, highlighted the potential of CPO-based data center architectures and the role of advanced semiconductor materials in enhancing energy efficiency and performance. Soitec recently joined the SEMI Silicon Photonics Industry Alliance (SEMI SiPhIA) to drive innovation, advance industry standards, and foster collaboration within the semiconductor industry.

The Spectrum-X Photonics switches, developed as part of these advancements, offer multiple configurations to meet the evolving needs of AI data centers. With options like 128 ports of 800Gb/s or 512 ports of 200Gb/s, these switches deliver impressive total bandwidth capabilities, catering to the increasing demands of next-generation workloads.