Metal oxide semiconductor-based negative capacitance field-effect transistors with a sub-threshold swing of below 30 mV/dec

Effective data processing and low power consumption of electronic devices have been demanded for artificial intelligence technologies. Here, we report IGZO-based negative capacitance field-effect transistors (IGZO NC-FETs) with stacked gate dielectrics composed of ferroelectric Hf_0.5Zr_0.5O₂ and high-k Al₂O_3. The manifestation of negative capacitance behavior was confirmed by the suppression of the thermionic subthreshold swing limit resulted in the improvement of low-power switching performance. The IGZO NC-FET occurs below 30 mV/dec of a steep subthreshold swing (SS), exceptionally across a gate bias range of ±1 V. Furthermore, high-k Al₂O₃ as a stabilizing layer suppresses the hysteresis, effectively coupled with a conventional ferroelectric layer.