Hot Carrier Degradation in MOSFETs at Cryogenic Temperatures Down to 4.2 K

Wide attention has been focused on cryogenic CMOS (cryo-CMOS) operation because of its promising improvement of devices’ and circuits’ performance and wide application prospects. However, hot carrier degradation (HCD) limits the long-term reliability of cryo-CMOS. This article investigates HCD in 0.18 $\mu \text{m}$ bulk CMOS at cryogenic temperature down to 4.2 K. Particularly, the relationship between HCD and the current overshoot phenomenon and the influence of substrate bias on HCD are discussed. Besides, we predict the lifetime of the device at 77 K and 4.2 K. It is concluded that cryogenic NMOS cannot reach the ten years’ commercial standard lifetime at standard $V_{DD}$ . And it is predicted that the reliability requirements can be reached when $V_{DD} \leq 1.768$ V and 1.734 V at 77 K and 4.2 K, respectively. Differently, the lifetime of PMOS is long enough even at low temperatures.