A Comparative Study on the Polarization, Reliability, and Switching Dynamics of HfO } -ZrO } -HfO } and ZrO } -HfO } -ZrO } Superlattice Ferroelectric Films

• Published in: IEEE transactions on electron devices 2023-03, p.1-6
• Main Authors: Li, Kaixuan, Peng, Yue, Xiao, Wenwu, Liu, Fenning, Zhang, Yueyuan, Feng, Ze, Dong, Hong, Liu, Yan, Hao, Yue, Han, Genquan
• Format: Article
• Language: English
• Subjects: Capacitors; Ferroelectric (FE); Frequency measurement; Hafnium oxide; HfO<inline-formula xmlns:ali="http://www.niso.org/schemas/ali/1.0/" xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"> <tex-math notation="LaTeX"> _{\text{2}}</tex-math> </inline-formula>; HZH; Iron; oxygen vacancy; polarization; Reliability; Switches; ZHZ; ZrO<inline-formula xmlns:ali="http://www.niso.org/schemas/ali/1.0/" xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"> <tex-math notation="LaTeX"> _{\text{2}}</tex-math> </inline-formula>
• ISSN: 0018-9383
• DOI: 10.1109/TED.2023.3248538

In this article, the effect of starting layer on the ferroelectric properties and reliability of HfO _{\text{2}} -ZrO _{\text{2}} -HfO _{\text{2}} (HZH) and ZrO _{\text{2}} -HfO _{\text{2}} -ZrO _{\text{2}} (ZHZ) superlattice (SL) films were systematically investigated. Compared with that of the ZHZ device, a higher value of remnant polarization ( \textit{P}_{\textit{r}}\text{)} for the HZH device was achieved. However, the ZHZ structure exhibits a better wake-up performance and frequency stability than HZH, as well as a higher inversion speed and more endurance cycles. Accordingly, a hybrid model involving ferroelectric (FE) polarization and interfacial ion migration is proposed. This study is helpful for understanding and optimizing the HfO _{\text{2}} -based FE films for non-volatile memory applications.