Examination of Ferroelectric FET for “Cold” Nonvolatile Memory

HfZrO_x-based Si n-/p-type ferroelectric field-effect transistors (n/pFEFETs) were investigated from 300 to 82 K with pulse measurements, which disclosed device physics at low temperatures. Moreover, FEFET shows extremely improved performance (read-after-write latency < 100 ns and write endurance<inline-formula> <tex-math notation="LaTeX">$10^{{10}}$ </tex-math></inline-formula> cycles with no device degradation) at 82 K. Even the lower write voltage is feasible at 82 K than at 300 K although the coercive field increases. The enhancement is attributed to frozen trap sites and increased coercive field at 82 K. Our work not only shows a deep understanding of device physics but also proposes that FEFET could be a promising cold memory.