Low‐Field‐Driven Domain Wall Motion in Wurtzite Ferroelectrics

Abstract

Abstract Wurtzite‐type nitride ferroelectrics emerge as a breakthrough platform for silicon‐compatible nonvolatile memory technology. However, the inherent polarization reversal mechanisms involving diatomic displacements introduce complex domain dynamics and elevate energy barriers, manifesting as excessive coercive fields ( E c ) and pronounced wake‐up effects that hinder reliable device operation. Here, these challenges are resolved by enabling the low‐field‐driven domain wall motion in representative wurtzite ferroelectrics (Al 0.75 Sc 0.25 N). In situ transmission electron microscopy measurements reveal that polarization switching proceeds via preferential domain‐wall transverse propagation perpendicular to the [0001] axis, preceding longitudinal propagation along the [0001] axis. First‐principles simulations quantify a striking 98% reduction in energy barrier for transverse migration (0.00188 eV f.u −1 ). Compared to longitudinal motion (0.092 eV f.u −1 ). This switching kinetic fundamentally challenges the conventional Kolmogorov‐Avrami‐Ishibashi model. By controlling nucleation polarity to promote the transverse motion of the domain wall, E c is reduced by 25%, with a high remanent polarization maintained and wake‐up effects eliminated across 6‐inch films. The methodology establishes a universal design principle for manipulating polarization switching in wurtzite ferroelectrics, paving the way for integrated low‐energy, high‐stability, uniformly‐performing ferroelectric devices in large‐scale complementary metal oxide semiconductor (CMOS) architectures.