Physical Insights on Steep Slope FEFETs including Nucleation-Propagation and Charge Trapping

We present a kinetics-based analysis of the steep slope operation of ferroelectric (FE) FETs built on (i) a statistical multidomain nucleation-propagation mechanism of FE polarization switching and (ii) charge trapping in the high- K FE oxide. With a hardware-validated compact model we predict the change in hysteresis direction, the steep slope and the transient behaviors observed in our I-V measurements on Hf 0 5 Zr 0 5 O 2 -based planar n-FEFETs. We find that the proposed field-independent propagation is essential in explaining the measured reverse-sweep steep slope and transient current drift. Furthermore, the model suggests that a higher polarization and accordingly a larger I-V hysteresis are induced upon increased trapping. Finally, we show that for hafnia-based FE oxides, reliability engineering of defect band is needed for obtaining steep slope in scaled logic-FEFETs.