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

We report on negative capacitance FETs (NCFETs) with a 1.8-nm-thick Zr-doped HfO 2 gate oxide layer fabricated on an FDSOI wafer. Hysteresis-free operation is demonstrated. When compared to a baseline that uses HfO 2 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 ( <tex-math notation="LaTeX">IOFF </tex-math> ) is observed at 30-nm channel length at constant <tex-math notation="LaTeX">ION </tex-math> . On the other hand, at matched <tex-math notation="LaTeX">I OFF </tex-math> , the NCFET provides a larger ON current at constant <tex-math notation="LaTeX">VDD </tex-math> . 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- <tex-math notation="LaTeX">K </tex-math> oxide layer used in ultra-scaled nodes.