Wideband-Noise-Matching Considerations for Cryo-CMOS LNAs

While references to cryogenic amplifiers date back to the early 1950s, cryo-LNAs still belong to a niche research field. However, with advances in quantum computing the interest in cryo-LNAs and cryo-CMOS LNAs is rising. The ultimate goal for cryo-LNAs is to exhibit the lowest-possible noise temperatures over their operating bandwidth. Unfortunately, wide LNA bandwidths and the unavailability of cryogenic transistor models hinder our progress towards that goal. This presentation reviews the progress towards tackling the two hindrances. First, this presentation reviews the techniques of simultaneous noise and power matching for wideband CMOS LNA. This is followed by a review of measurement methods of cryogenic noise parameters for developing better transistor models.