Zhang Siqing, Liu Huan, Zhou Jiuren, Liu Yan, Han Genquan, Hao Yue
State Key Discipline Laboratory of Wide Band Gap Semiconductor Technology, School of Microelectronics, Xidian University, Xi'an, 710071, China.
Nanoscale Res Lett. 2021 Feb 2;16(1):21. doi: 10.1186/s11671-020-03468-w.
Here we report the ZrO-based negative capacitance (NC) FETs with 45.06 mV/decade subthreshold swing (SS) under ± 1 V V range, which can achieve new opportunities in future voltage-scalable NCFET applications. The ferroelectric-like behavior of the Ge/ZrO/TaN capacitors is proposed to be originated from the oxygen vacancy dipoles. The NC effect of the amorphous HfO and ZrO films devices can be proved by the sudden drop of gate leakage, the negative differential resistance (NDR) phenomenon, the enhancement of IDS and sub-60 subthreshold swing. 5 nm ZrO-based NCFETs achieve a clockwise hysteresis of 0.24 V, lower than 60 mV/decade SS and an 12% IDS enhancement compared to the control device without ZrO. The suppressed NC effect of AlO/HfO NCFET compared with ZrO NCFET is related to the partial switching of oxygen vacancy dipoles in the forward sweeping due to negative interfacial dipoles at the AlO/HfO interface.
在此，我们报道了基于ZrO的负电容（NC）场效应晶体管，在±1V电压范围内具有45.06mV/十倍频程的亚阈值摆幅（SS），这可为未来电压可扩展的NCFET应用带来新机遇。Ge/ZrO/TaN电容器的类铁电行为被认为源于氧空位偶极子。非晶HfO和ZrO薄膜器件的NC效应可通过栅极泄漏电流的突然下降、负微分电阻（NDR）现象、漏极电流（IDS）的增强以及低于60的亚阈值摆幅来证明。基于5nm ZrO的NCFET实现了0.24V的顺时针滞后，低于60mV/十倍频程的SS，与无ZrO的对照器件相比，IDS增强了12%。与ZrO NCFET相比，AlO/HfO NCFET的NC效应受到抑制，这与AlO/HfO界面处的负界面偶极子导致氧空位偶极子在前向扫描中的部分开关有关。
