Nano-scaled Ge FinFETs with low temperature ferroelectric HfZrOx on specific interfacial layers exhibiting 65% S.S. reduction and improved ION

Ge n- and p-FinFETs with different interfacial layer ferroelectric HfZrO
_x
(IL-FE-HZO) gate stacks have been demonstrated systematically by various annealing conditions for the first time. Microwave annealing (MWA) not only shows enhanced FE characteristics but also suppresses the gate leakage and Ge interdiffusion compared with conventional rapid thermal annealing (RTA). While HZO on Al
₂
O
₃
IL results in paraelectric behavior, HZO on GeO
_x
IL exhibits significant FE. High I
_on
/I
_off
(> 107) and low subthreshold slope (S.S. ~ 58 mV/dec.) are demonstrated by a Ge nFinFET with a gate length (L
_g
) of 60 nm and a FE-HZO/GeO
_x
gate stack.