Sub-kT/q Switching in Strong Inversion in PbZr0.52Ti0.48O₃ Gated Negative Capacitance FETs

Hysteretic switching with a sub-kT/qsteep slope (13 mV/decade at room temperature) is experimentally demonstrated in MOSFETs with PbZr0.52Ti0.48O3as a ferroelectric (FE) gate insulator, integrated on a silicon channel with a nonperovskite high-kdielectric (HfO2) as a buffer interlayer. The steep switching is independent of drain bias. For the first time, sub-kT/qswitching due to FE negative capacitance is observed not at low currents, but in strong inversion (Id~100μ A/μ m). Steep switching in strong inversion provides an important point of consistency with the predictions of the Landau–Devonshire theory and the Landau–Khalatnikov equation.