In2O3 Nanowire Field-Effect Transistors with Sub-60 mV/dec Subthreshold Swing Stemming from Negative Capacitance and Their Logic Applications.

ABSTRACT

Heat dissipation is a key issue for scaling metal-oxide-semiconductor field-effect transistors (MOSFETs). The Boltzmann distribution of electrons imposes a physical limit on the subthreshold swing (SS), which impedes both the reduction of the switching energy and the further increase of the device density. The negative capacitance effect is proposed to rescue MOSFETs from this phenomenon called "Boltzmann tyranny". Herein, we report In2O3 nanowire (NW) transistors with SS values in the sub-60 mV/dec region, which utilize the ferroelectric P(VDF-TrFE) as the dielectric layer. An ultralow SS down to ∼10 mV/dec is observed and spans over 5 orders of magnitude in the drain current. Meanwhile, a high on/off ratio of more than 108 and a transconductance ( gm) of 2.3 µS are obtained simultaneously at Vd = 0.1 V. The results can be understood by the "voltage amplification" effect induced from the negative capacitance effect. Moreover, the steep slope FET-based inverters indicate a high voltage gain of 41.6. In addition to the NOR and NAND gates, the Schmitt trigger inverters containing only one steep slope FET are demonstrated. This work demonstrates an avenue for low-power circuit design with a steep SS.