Biaxial Strain based Performance Modulation of Negative-Capacitance FETs

Abstract

In this work, we report device simulations conducted to study the performance of biaxially strained ferroelectric-based negative capacitance FETs (NCFETs). We adopted PbZr 0.5 Ti 0.5 O 3 (PZT) and HfO 2 as ferroelectric materials and applied biaxial strain using the first-principles method. It was found that PZT and HfO 2 show different trends in the negative capacitance (NC) region under biaxial strain. Biaxial strain strongly affects the NC of PZT, whereas HfO 2 is not as susceptible to biaxial strain as PZT. When no strain is applied, HfO 2 -based NCFETs exhibit a better performance than PZT-based NCFETs. However, the subthreshold slope and ON-state current are improved in the case of PZT-based NCFETs when the compressive biaxial strain is increased, whereas the performance of HfO 2 based NCFETs is slightly degraded. In particular, the negative drain-induced barrier lowering and negative differential resistance vary considerably when compressive strain is applied to PZT-based NCFETs.