  Conventional CMOS technology operated at cryogenic conditions has recently
attracted interest for its uses in low-noise electronics. We present one of the
first characterizations of 180 nm CMOS technology at a temperature of 100 mK,
extracting I/V characteristics, threshold voltages, and transconductance
values, as well as observing their temperature dependence. We find that CMOS
devices remain fully operational down to these temperatures, although we
observe hysteresis effects in some devices. The measurements described in this
paper can be used to inform the future design of CMOS devices intended to be
operated in this deep cryogenic regime.
