Semiwise has developed transistor models for the GlobalFoundries 22FDX that cover operation at cryogenic temperatures using a combination of its own re-centering tool and Synopsys’ Senaturus TCAD software.
The Semiwise re-centering technology revolves around a combination of transistor measurements and TCAD simulations. The company has worked on this modelling chiefly to support the development of control circuitry for quantum computers as they scale up in qubit capacity. Today’s control boards are generally linked to the cryogenic chamber by long, high-bandwidth cables to avoid CMOS dissipation heating the delicate qubit circuits. If designers ca locate the controllers closer to the quantum operations they can reduce latency and use more complex error correction in practical systems.
Semiwise said the models can also be used to design CMOS chips for data centres that will operate reliably at liquid nitrogen temperatures. A recent study from Synopsys has shown that if processors and other chips are operated at 77K, the power dissipation can be reduced around seven-fold at equivalent speed.
The new models are needed because this temperature reduction results in drastic changes of the transistor characteristic compared to room-temperature operation. As the process provides FD-SOI transistors, Semiwise sees the GF 22FDX platform as particularly suitable for cryogenic circuits: the transistor parameters can be altered dynamically by electrical back biasing to compensate for switching-speed reductions at low temperatures.
“Cryogenic chip design will not only unleash the true power of quantum computers but will increase significantly the energy efficiency of data centres in the transition to a net zero economy,” said Semiwise CEO Professor Asen Asenov.