High-Frequency and Noise Performances of 65-nm MOSFET at Liquid Nitrogen Temperature

In this paper, the high-frequency properties of MOSFETs at low-temperature operation are investigated through measurements and electrical simulations. The experimental results show that the device achieves a 335-GHz f
_max
and a 300-GHz f
_t
when operating at low temperature (78 K), which constitutes, respectively, a 78% and 34% improvement compared to the room temperature performances (296 K). The minimum noise figure NF
_min
decreases from 1.4 dB (296 K) to 0.5 dB at 30 GHz (78 K), while the associated gain increases from 8 to 12 dB