Wake-Up Free La-Doped HfO<sub>2</sub>-ZrO<sub>2</sub> Ferroelectrics Achieved With an Atomic Layer-Specific Doping Technique
Zeping Weng, Yiming Qu, Zhangsheng Lan, Jirong Liu, Mingji Su, Jianguo Li, Yaru Ding, Choonghyun Lee, Zhao Liang, Yi Zhao
Abstract
In this letter, wake-up free La-doped HfO2-ZrO2 (HZO) ferroelectrics are experimentally fabricated using an atomic layer-specific doping (ALSD) technique, which selectively introduces La dopants at effective locations to facilitate the formation of ferroelectric orthorhombic phase. With this technique, robust La-doped HZO ferroelectric devices that are mostly free from the undesired wake-up effect and anti-ferroelectricity were demonstrated over a large La doping range (from 2.9 to 11.5%). Moreover, large remanent polarization and good endurance were achieved at the same time (>107 cycles). The outstanding performances can be attributed to the effective stabilization of ferroelectric orthogonal phase and the suppression of tetragonal phase, through controlling of the dopants’ local environment. Thus, ALSD is an effective approach to achieve reliable, wake-up free and CMOS-compatible HZO-based ferroelectrics.