TSMC Bets on Emerging Silicon Photonics Technology

Despite the sluggish performance of the global semiconductor industry this year due to high interest rates and inflation, industry leader TSMC (2330) is still actively laying out the emerging semiconductor field of “silicon photonics chips”, aiming for business opportunities next year. According to reports, TSMC is not only actively promoting the development of silicon photonics technology, but also negotiating with major customers like Broadcom and Nvidia to jointly develop new products applying silicon photonics technology. The two sides plan to produce a new generation of silicon photonic chips, covering processes from 7nm to 45nm, and expect to receive the first batch of orders in the second half of 2024.

According to TSMC Vice President Dr. Y.J. Mii, a good silicon photonics integration system can not only solve the two major challenges of AI – energy efficiency and computing power, but also usher in a brand new stage in semiconductor development. He believes that powerful computing capabilities are required to run large language models and other AI computing tasks, and a more advanced, more integrated silicon photonic system is the key driving force.

So where does the advantage of silicon photonics technology lie? We know that integrated circuits cram billions of transistors onto chips to perform computations. Silicon photonics technology, on a silicon chip, converts “electrical signals” into “optical signals”, achieving electrical-to-optical signal transmission.

Compared with traditional electronic transmission using copper wires, photonic transmission has two main advantages:

  1. First, the speed of light is fast. The speed of light is the fastest physical constant known in the universe so far. By utilizing the transmission of photons in the medium, the transmission speed of information can be greatly improved, far exceeding the speed of electrons.
  2. Second, photonic transmission avoids the signal attenuation and noise interference caused by increasing line length in electronic transmission. Photons can maintain signal quality when propagating in optical fibers or waveguides.

Additionally, compared to copper wires, photonic transmission can also reduce the energy consumption and heat generation during transmission. This has positive implications for heat dissipation in data centers.

Thus, silicon photonics technology can significantly improve computation and transmission speeds while reducing energy consumption, resolving bottlenecks in current computer development, and is therefore regarded as a major technical direction for next-generation semiconductors.

In fact, silicon photonics has become a hot spot in the semiconductor industry. Companies like Intel, Cisco, and IBM are also laying out silicon photonics. In 2021, Nvidia acquired Mellanox for $6.9 billion, optimistic about its optical networking technology applications in data centers and other fields.

Currently, silicon photonics technology has been preliminarily commercialized in applications like data center optical communications. With the emergence of 800G or even higher speed transmission demands, power and heat dissipation issues will become increasingly challenging. It is expected that silicon photonics technology will play a greater role in tackling this problem.

Industry analysis believes that silicon photonics is indeed an inevitable trend for future development, with broad application prospects in data centers, supercomputing, autonomous driving, national defense and other systems. However, there are still technical barriers to overcome for commercialization. Specifically:

  1. The process platform is still not mature enough. Further improving process stability and consistency is required to achieve large-scale commercialization.
  2. There is still much room for improvement for nanoscale photonic devices, and the integration density of photonic modules needs to be increased.
  3. Optoelectronic integration designs at the system level also need continuous optimization.

In summary, silicon photonics technology will catalyze a new round of revolution and upgrade in the semiconductor industry. TSMC’s bet on this emerging technology is conducive to maintaining its leadership in advanced processes. Next, the continuous improvement of the R&D ecosystem will be the key to realizing the commercialization of silicon photonics technology. It is expected that in the next few years, with the joint efforts across the industry chain, we could see the ramping up of silicon photonic chip production and expanding application, thus driving the development of the semiconductor industry and information technology.