From transceivers to speed-of-light AI
Since 1985, silicon photonics has progressed from the initial development of high confinement waveguides to strategically incorporate CMOS techniques, establishing its dominance in the transceiver space. In the coming years, it has the potential to expand to a wide range of innovative applications.
BY Martin Vallo, senior analyst in photonics at Yole
Since early 2023, there has been a lot of hype around – and massive investments into – silicon photonics, especially optical computing, optical I/O, and diverse sensing applications. It seems logical that primary technologies in various applications will be replaced relatively quickly by optical-based designs and architectures. The giants forecast that optics will be necessary and become ubiquitous relatively soon, while startups are developing new applications through R&D. So, can we expect this prediction to be realised any time soon?
While there are many arguments about the necessity of photonics coupled with electronics, the largest silicon photonics market – datacom pluggables – generates only around 12 percent of datacom transceiver revenue (projected to reach 30 percent by 2028). The semiconductor market is suffering from an extended period of decline, leading to more pragmatic buying behaviour on the part of customers. DC operators prefer long-established and low-cost technology solutions. Yole Intelligence’s market research shows that silicon photonics is not yet a primary technology, even for intra-data-centre interconnects with up to 500 m reach.
Figure 1:Growth forecast for various silicon photonicsapplications.Credit: Yole Intelligence.
In this context, silicon photonics remains a technology in active development, with a wide array of potential applications, hinting at promising opportunities on the horizon. In the coming decade, frontrunners will emerge, leading to industry consolidation. Nevertheless, the broad spectrum of applications will ensure abundant opportunities for the technology to expand and proliferate.
Yole Group, in its new Silicon Photonics 2023 report, estimated the silicon photonics PIC market was worth US$68 million in 2022 and is forecast to generate more than US$600 million in 2028 at a 44 percent Compound Annual Growth Rate for 2022-2028 (CAGR2022-2028). This growth will mainly be driven by 800G high-data-rate pluggable modules for increased fibre-optic network capacity. Additionally, projections of rapidly growing training dataset sizes show that data will need to use light to scale ML models using optical I/O in ML servers.
Substantial data centre requirements, particularly in the domains of artificial intelligence (AI) and machine learning (ML), are expected to fuel the ongoing demand for swifter applications and computations over the next decade. With the conventional processor-centric computing architecture and copper interconnects, the state-of-the-art chips based on 3nm technology are approaching their physical limitations, while the necessity for faster data transmission has surged. Silicon photonics, with its ability to facilitate high-speed communication, has therefore become a prime focus.