Bottom Electrode Crystallinity-Driven Enhancement of Switching Behavior in Scaled (Al 0.9 Sc 0.1 )N Films

High Resolution Image Download MS PowerPoint Slide Ferroelectric wurtzite-structure films serve as pivotal building blocks for next-generation microelectronics. However, their inherently high coercive fields severely limit their implementation in low-power device architectures. Clarifying polarization switching mechanisms and identifying key performance-regulating parameters are, therefore, critical to advancing wurtzite-type ferroelectric materials. In this paper, we discuss the switching kinetics across atomic, nano, and macroscopic levels. To improve the switching performance of scaled (Al 0.9 Sc 0.1 )N films, we investigate the effect of a bottom electrode modified via post-deposition annealing on polarization switching characteristics. Our results reveal that enhanced electrode crystallinity enables precise tuning of the c / a axis ratio and in-plane compressive strain in (Al 0.9 Sc 0.1 )N films. Remarkably, the scaled (Al 0.9 Sc 0.1 )N films not only preserve the Kolmogorov–Avrami–Ishibashi (KAI) switching mode but also achieve a significant one-order-of-magnitude acceleration in switching speed compared to films grown on as-deposited Pt. Moreover, reduced electrode area promotes faster switching behavior, and thinner (Al 0.9 Sc 0.1 )N layers deposited on annealed Pt electrodes show superior switching speed relative to those on pristine Pt electrodes. The present study establishes optimization of bottom electrode quality as an effective strategy to overcome scaling challenges in (Al 0.9 Sc 0.1 )N films, laying a reliable foundation for their integration into high-density, high-speed ferroelectric microelectronic devices.