Back-End of Line Compatible HZO/ZrO 2 Ferroelectric Capacitor Achieving 2P r of 51.1 μC/cm 2 , High- k (~48.4), and Endurance Exceeding 10 11 Cycles Under Low-Voltage Operation

作者：Lei Wang, Kangli Xu, Yongkai Liu, Aolin Yuan, Jiajie Yu, Jialin Meng, Hao Zhu, Qingqing Sun, David Wei Zhang, Tianyu Wang, Lin Chen · 发表于：IEEE Electron Device Letters · 年份：2025 · DOI：10.1109/led.2025.3610820 · 被引用次数：1 · 研究领域：Ferroelectric and Negative Capacitance Devices

This study is motivated by the persistent challenge of developing dielectric (DE) materials that simultaneously satisfy the high dielectric constant of eDRAM-driven and robust ferroelectric (FE) properties required by FeRAM within a low thermal budget (≤400 °C) for application in Back-End of Line (BEOL) dual-mode cache/near memory processing units. Here, we address this challenge by a W/Hf0.5Zr0.5O2(HZO)/ZrO2/W structure ferroelectric capacitor and optimizing the thickness ratio of the ZrO2and HZO layers to construct near morphotropic phase boundary (MPB). The (HZ)6Z4 configuration, with a 4-nm ZrO2top layer and a 6-nm HZO layer, exhibited enhanced performance with remanent polarization (2Pr~51.1 μC/cm²) and dielectric constant (k~48.4) after RTP at 350 °C. The (HZ)6Z4 sample also demonstrates low-voltage operation (~1.7 V), high endurance (>1011cycles) due to a reduced coercive field (Ec~1.0 MV/cm), and fast polarization switching (~121 ns). These results show that (HZ)6Z4 nanostack can effectively balance the performance required for low-power BEOL dual-mode cache/near-memory processing units, paving the way for the development of next-generation advanced logic and memory devices.