High performance and nearly wake-up free HfZrOferroelectric capacitor realized by middle layer strategy with BEOL compatibility.

HfZrO(HZO) has drawn great attention owing to its excellent ferroelectricity, sub-10 nm scalability, and CMOS compatibility. With regard to increasingly restrict thermal budget and power consumption, conventional HZO films need further optimization to meet these demands. Here, we propose a middle layer (ML) strategy aiming to enhance ferroelectricity and inhibit wake-up effect of ferroelectric (FE) capacitors compatible with back-end of line under the low operating electric field. ZrO, HfO, and AlOwere integrated into HZO film as different MLs. Among them, the device with ZrOML achieves the excellent double remnant polarization (2) of 41.7C cmunder the operating electric field of 2 MV cm. Moreover, ultralow wake-up ratios of around 0.08 and 0.05 were observed under 2 MV cmand 3 MV cm, respectively. Additionally, the FE capacitor with ZrOML demonstrated an enhanced reliability characterizations, including a stable 2of 40.7C cmafter 4.3 × 10cycles. This work provides the perspective to optimize both the ferroelectricity and reliability, while maintains the ultralow wake-up ratio in HfO-based FE through ML engineering.