Negative Capacitance FET With 1.8-nm-Thick Zr-Doped HfO2 Oxide

Abstract

We report on negative capacitance FETs (NCFETs) with a 1.8-nm-thickZr-doped HfO2 gate oxide layer fabricated on an FDSOI wafer. Hysteresis-free operation is demonstrated. When compared to a baseline that uses HfO2 gate oxide with the same thickness, a subthreshold swing (SS) steeper by more than 20 mV/decade and larger than 10X reduction in the OFF current (I-OFF) is observed at 30-nm channel length at constant I-ON. On the other hand, at matched I-OFF, the NCFET provides a larger ON current at constant V-DD. Our results indicate that the beneficial characteristic offered by the NCFETs can be obtained at scaled channel lengths, while using oxide layers whose thickness is comparable to the high-K oxide layer used in ultra-scaled nodes.