IBM Breaks the 1NM Barrier With New ‘Nanostack’ Architecture

IBM is not the first name that comes to mind when it comes to chip design, but in fact it is on the bleeding edge of semiconductor development, thanks in part to its multi-decade partnership with Rensselaer Polytechnic Institute.

And once again, IBM has unveiled a first: it has developed the first transistor technology below one nanometer, beating Intel and TSMC in the race to shrink the transistor even further.

The technology, which IBM calls Nanostack, is a three-dimensional transistor design that enables the world’s first sub-1 nanometer chip technology. The technology, detailed by IBM Research, is a departure from the semiconductor industry’s established practice of shrinking transistors in two dimensions.

Instead, Nanostack increases transistor density through 3D stacking, a technique used in High Bandwidth Memory (HBM) for some time now. By building upward and stacking transistors vertically, IBM can create a more compact and efficient structure.

The result of IBM’s research chip packs nearly 100 billion transistors onto a chip roughly the size of a fingernail—though they didn’t say which finger. That’s almost double the density of the company’s 2-nanometer technology announced in 2021. IBM says the design can deliver up to 50% higher performance and up to 70% lower power consumption than the 2nm generation.

Nanostack is built on IBM’s nanosheet transistor technology, a new chip design that replaces FinFET technology in transistor design. Nanosheets improve transistor performance by surrounding the channel with the gate on all sides. The new design required advances on several fronts, including wafer bonding, multi-layer CMOS integration and new bonding layers between the transistors.

IBM argues the new architecture is well suited for AI infrastructure, from data centers where training and inference take place to laptops where AI processors run models locally.

IBM made it clear that Nanostack is a research-stage technology rather than a commercial product. The company estimated that chips based on the architecture could reach production in approximately five years. Intel is currently at 1.8 nanometers, so it’s very likely to be at 0.7 nanometers within five years.

Although IBM’s chip manufacturing business is now limited — it still makes POWER processors for its server line and Telum II processors for its mainframes — it also shares and licenses technology with chipmakers such as TSMC and Samsung.