Cryogenic Characteristics of MOSFET in Monolithic Silicon-Photonic Process

Characteristics of transistors from two commercial monolithic silicon-photonic processes are evaluated for the first time down to 2.5 K cryogenic temperatures. dc characterization is implemented on different types of devices. Key design parameters are extracted and analyzed with the corresponding low-temperature effects, including the increase in both threshold voltage and carrier mobility, the decrease of subthreshold swing (SS), and the severe kink effect in floating-body (FB) devices. The characterization of ring oscillators (ROs) shows the average gate delay improves by approximately 21%. The random telegraph noise (RTN) is measured and analyzed in both time and frequency domains, showing that the band tail states are likely the source of the extra noise at deep cryogenic temperature, leading to the increase of corner frequency by $10\times $ in the overall noise power spectral density (PSD).