Performance improvements in complementary metal oxide semiconductor devices and circuits based on fin field‐effect transistors using 3‐nm ferroelectric Hf <sub>0.5</sub> Zr <sub>0.5</sub> O <sub>2</sub>
Zhaohao Zhang, Yan-Na Luo, Gaobo Xu, Jiaxin Yao, Zhenhua Wu, Hongbin Zhao, Qingzhu Zhang, Huaxiang Yin, Jun Luo, Wen‐Wu Wang, Hailing Tu
Abstract
Abstract In this work, a conventional HfO 2 gate dielectric layer is replaced with a 3‐nm ferroelectric (Fe) HZO layer in the gate stacks of advanced fin field‐effect transistors (FinFETs). Fe‐induced characteristics, e.g., negative drain induced barrier lowering (N‐DIBL) and negative differential resistance (NDR), are clearly observed for both p‐ and n‐type HZO‐based FinFETs. These characteristics are attributed to the enhanced ferroelectricity of the 3‐nm hafnium zirconium oxide (HZO) film, caused by Al doping from the TiAlC capping layer. This mechanism is verified for capacitors with structures similar to the FinFETs. Owing to the enhanced ferroelectricity and N‐DIBL phenomenon, the drain current ( I DS ) of the HZO‐FinFETs is greater than that of HfO 2 ‐FinFETs and obtained at a lower operating voltage. Accordingly, circuits based on HZO‐FinFET achieve higher performance than those based on HfO 2 ‐FinFET at a low voltage drain ( V DD ), which indicates the application feasibility of the HZO‐FinFETs in the ultra‐low power integrated circuits.