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A compact analytical model is reported capturing the effects of Coulomb Blockade and charge quantization on the drain current characteristics of a MOSFET-based semiconductor quantum dot at cryogenic temperatures. It is implemented as a Verilog-A add-on to the foundry-provided MOSFET model to facilitate potential integration in any design kit and allow for simulation of quantum processors that integrate qubits and control electronics on the same die. The model was verified in the 6-50 K temperature range on the measured I-V characteristics of a nanoscale p-MOSFET fabricated in production 22nm FDSOI CMOS technology.

An approach is proposed to realize large-scale, “high-temperature” and high-fidelity quantum computing integrated circuits based on single- and multiple-coupled quantum-dot electron- and hole-spin qubits monolithically integrated with the mm-wave spin manipulation and readout circuitry in a commercial CMOS technology. Measurements of minimum-size 6 nm $\times20$ nm $\times80$ nm Si-channel n-MOSFETs (electron-spin qubit), SiGe-channel p-MOSFETs (hole-spin qubit), and double quantum-dot complementary qubits reveal strong quantum effects in the subthreshold region at 2 K, characteristic of resonant tunneling in a quantum dot. S-parameter measurements of a transimpedance amplifier (TIA) for spin readout show an improved performance from 300 K to 2 K. Finally, the qubit-with-TIA circuit has 50- $\Omega $ output impedance and 78-dB $\Omega $ transimpedance gain with a unity-gain bandwidth of 70 GHz and consumes 3.1 mW.

The high frequency performance of all active and passive devices in a production 22nm FDSOI CMOS technology was measured up to 40 GHz over temperature down to 3.3 Kelvin, targeting applications in cryogenic and quantum computing ICs. It was found that the quality factor of the passives and the f T and f MAX of both p- and n-MOSFETs improved at 3.3 K. More importantly for circuit design, the peakf T and peak-f MAX current densities, and the MOM capacitor and polysilicon resistor values show no variance with temperature. This information and the measured I-V characteristics of electron and hole single- and double-quantum dot structures, measured at 2 K and representative of qubits, were used to design monolithically integrated double quantum dots with readout transimpedance amplifiers output matched to 50 Ω. Transimpedance gain, S 21 , and bandwidth of 108 dBΩ, 19 dB, and 7.5 GHz, respectively, were measured at 300 K with only 4.5 mW power consumption and S 22 < -10 dB up to 60 GHz.