IBM demonstrated a concept nanosheet transistor at the 2023 IEEE International Electron Devices Meeting (IEDM) that improves performance by nearly 100% at nitrogen's boiling point of 77 Kelvin (-196°C). Given that the manufacturing, safe transportation, storage and use of liquid nitrogen have been relatively industrialized and large-scale, this research and development achievement may open up new types of chips that can achieve top performance under liquid nitrogen cooling conditions.
A new generation of artificial intelligence high-performance computing accelerators can instantly double performance in a liquid nitrogen environment simply by developing a new cooling solution for data centers.
Nanosheet transistors are the next step in the evolution of fin field-effect transistors (FinFETs), which have been driving semiconductor foundry development since 16nm and whose technological limits may be reached at 3nm. Nanosheets are expected to debut on 2nm nodes such as TSMC N2 and Intel 20A.
At an operating temperature of 77K, IBM's nanosheet devices are said to nearly double performance due to less scattering of charge carriers, thereby reducing power consumption. Reducing scattering lowers the resistance in the wire, allowing electrons to move through the device faster. While reducing power consumption, the device can drive greater current at a given voltage. Cooling also improves the sensitivity of the device between its on and off positions, so less power is required to switch between the two states, reducing power. Reduced power consumption means transistor width can be reduced, thereby increasing transistor density or shrinking chip size.
Currently, IBM is grappling with the technical problem of a transistor's threshold voltage, which is the voltage required to form a conductive path between the source and drain.