The Future of Semiconductors: A Roadmap to 2033 and Beyond

As we approach the mid-2020s, the semiconductor industry is poised for significant transformations in the next decade. The latest roadmap from Belgium-based nanotech research institution Imec outlines a challenging road ahead for chip manufacturers, with major advancements expected by 2033. In this article, we'll explore the potential technologies that could shape the future of semiconductors and what they mean for industries like computing, consumer electronics, and more.

The Next Evolution in CMOS Transistors

Imec's roadmap points to a significant shift in transistor technology starting around the A7 node, around 2033. This transition will be driven by the development of complementary field-effect transistors (CFETs), which promise to halve the area of some circuits. CFETs would stack two transistors on top of each other, allowing for more efficient operation and reduced power consumption.

The likely path to CFETs involves building both transistors at once, using a combination of silicon and silicon-germanium layers. This process requires significant advancements in lithography and processing techniques, but the potential rewards are substantial. According to Imec's chief technology officer, Paul Heremans, "Our research programs do de-risking of technology options," which will help to accelerate the development of CFETs.

The World's Largest Chipmakers on Track for CFETs

Industry leaders Intel, Samsung, and TSMC are already working towards making CFET-based chips manufacturable. Each company has constructed prototype CFET chips, with TSMC demonstrating a super compact memory cell and a key test circuit called a ring oscillator at the IEEE International Electron Devices Meeting last December.

Samsung will further advance its CFET technology in June 2024, with a device that's simultaneously the smallest yet and made with six layers of nanosheets. However, many questions remain about how best to make CFETs, including the challenges posed by electrically separating the top and bottom transistors from each other.

2D Semiconductors on the Horizon

Imec expects CFETs to follow a similar evolution to recent technology introductions, such as FinFET 15 years ago and the nanosheet transistor, which is entering commercial products now. This means an initial launch, followed by efforts to boost density and performance, and finally a push for further improvements in power efficiency.

After that, probably around 2041, Imec expects industry to swap the silicon in CFETs for something new, such as one or more types of 2D semiconductors. Unlike with the move to CFETs, 2D semiconductors would mostly be about improving power consumption, rather than squeezing more devices onto a chip.

The Benefits of 2D Semiconductors

Imec's chief technology officer highlights the potential benefits of 2D semiconductors in reducing power consumption. "A small reduction in voltage has an outsized effect on reducing power," he explains. With 2D semiconductors, transistors could use less voltage to control current flow, leading to further efficiency boosts.

Interconnects, Packaging, and CMOS 2.0

As CFETs arrive when Imec predicts they will, industry will be poised for significant advancements in interconnects, packaging, and chip design. Intel has already moved power-delivering interconnects beneath the layer of silicon transistors on a chip, paving the way for further innovations.

In 2033, Imec expects that industries like computing and consumer electronics will see a major boost in performance and efficiency thanks to the development of CMOS 2.0. This involves stacking multiple chips made with different technologies together, as well as fusing individual layers of transistors into one chip for specific functions.

Conclusion

The next 15 years of Moore's Law look like they'll be shaped by significant advancements in transistor technology. From CFETs to 2D semiconductors, the semiconductor industry is poised for a major transformation that will have far-reaching implications for industries and consumers alike. As Imec continues to drive innovation and de-risking in this area, we can expect even more exciting developments on the horizon.