Unlocking Ferroelectricity in Scalable AlBN Films via Plasma‐Enhanced Atomic Layer Deposition

Ferroelectric metal nitride thin films, particularly AlScN, have recently emerged as transformative materials for next‐generation electronics, owing to their high polarization, tunable coercive fields, exceptional endurance, and thermal stability. In pursuit of device miniaturization, atomic layer deposition (ALD) offers unparalleled advantages by delivering angstrom‐level thickness precision and conformality on complex 3D architectures; yet most prior studies have relied on physical vapor deposition of films several hundred nanometers thick. Here, we demonstrate the plasma‐enhanced ALD of B‐doped AlN (AlBN) thin films, where systematic control of the AlN:BN cycle ratio precisely regulates B concentration, enabling direct elucidation of the interplay between composition, crystallinity, and ferroelectric behavior. Density functional theory provided mechanistic insight into B incorporation pathways, while piezoresponse force microscopy confirmed local polarization switching across all compositions, with the optimized AlBN film exhibiting the most pronounced P–E hysteresis loop. This composition further displayed low leakage current and endurance exceeding 10 5 switching cycles. Collectively, these findings establish PEALD‐grown AlBN as a robust ferroelectric nitride and highlight its promise as a CMOS‐compatible, scalable alternative to AlScN for next‐generation non‐volatile memory technologies.