UK consortium tapes out cryo-SRAM

A UK cryogenic-CMOS research project has taped out its first demonstrator chip for core memory IP expected to be able to operate at close to absolute zero.

SureCore, which is the lead partner on the Innovate UK-funded project “Development of CryoCMOS to Enable the Next Generation of Scalable Quantum Computers”, has designed an SRAM that can run at temperatures from 77K (-196°C) down to the near absolute zero temperatures needed by quantum computers. In addition, both standard cell and I/O cell libraries have been re-characterised for operation at cryogenic temperatures to help enable an industry standard RTL-to-GDSII physical design flow to be used.

“Currently, expensive bulky cabling connects room temperature control electronics to the qubits housed in the cryostat. Enabling quantum-computer developers to be able to exploit the fabless design paradigm and create their own custom cryogenic control SoCs, which can be housed with the qubits inside the cryostat, is a game-changer. Immediate benefits include cost, size and, most importantly, latency reduction. The next step will be characterising the demonstrator chip at cryo temperatures to further refine and validate the models to help improve the performance,” claimed Paul Wells, sureCore’s CEO.

The use of CMOS in cryogenic systems helps avoid the need to move to superconductor-based circuits that remain difficult to integrate and which are very limited in terms of practical memory capacity.

Consortium member Universal Quantum expects its modular ion-trap-based architecture to benefit from the cryogenic IP developed by the project. Though its technology does not require near-zero temperatures, its hardware still needs to operate at 70K.

“We are positioning ourselves as the go-to experts in the field of cryogenic IP development and, along with our consortium partners, we are enabling the UK to be seen as a centre of excellence for quantum computing. By working as a focused expert team, the project expects to be able to demonstrate such results in the coming year rather than the many years it would have taken without the support of Innovate UK,” Wells added.