Impact of Thickness Dependent Ferroelectric and Interface Charge Variation on Device-to-Device Variation in Ferroelectric FET

In this work, the film thickness-dependent threshold voltage
$(V_{\text{TH}})$
variation is investigated theoretically through statistical Monte Carlo simulation. An improved VTH variation is found in the 6 nm
$\text{Hf}_{0.5}\text{Zr}_{0.5}\mathrm{O}_{2}$
(HZO) gate insulator under the coupling effect of ferroelectric parameters and interface charge density fluctuations, in comparison to thicker HZO films. The increase in trap density significantly deteriorates the
$V_{\text{TH}}$
variation, which can be mitigated by the enlarged charge response in the thin film. This work provides a guideline for variation performance improvement in building reliable ultra-scale integrated circuits.