2026/01/23 by Anna N. Morozovska, Eugene А. Eliseev, Eugene A. Eliseev +5 · 1 voice
Materials Science · Engineering · #Ferroelectric and Piezoelectric Materials #Ferroelectric and Negative Capacitance Devices #Acoustic Wave Resonator Technologies
paper · pdf · doi:10.1002/adfm.76920
ABSTRACT Heterogeneous nucleation from defects dominates the electric field required for polarization switching of ferroelectrics. Here, we consider the switching of a nominally non‐switchable polar thin film of AlN due to the proximity effect arising from embedded ferroelectric nanoclusters of Al 1‐x Sc x N. Using Landau–Ginzburg–Devonshire theory and finite element modeling, we study the influence of nanocluster shape on polarization switching and domain nucleation emerging in AlN. The ferroelectric nanocluster boundary is modeled as a thin layer transitioning from Al 1‐x Sc x N to AlN. We analyze the conditions under which polarization switching in the AlN film with embedded Al 1‐x Sc x N nanoclusters occurs at external electric fields significantly lower than its experimental dielectric breakdown field. In the presence of spike‐like Al 1‐x Sc x N nanoclusters, the proximity effect enables switching in AlN and significantly reduces the coercive field of the nanocomposite. The internal field, which is depolarizing inside the AlN (due to its larger spontaneous polarization) and polarizing within the ferroelectric Al 1‐x Sc x N nanoclusters (due to its smaller spontaneous polarization), lowers the potential barrier in the clusters and nucleates nanodomains at the Al 1‐x Sc x N−AlN interface, forming localized regions of reversed polarization. Proximity effect can thus provide a pathway toward “thawing” previously “frozen” ferroelectrics through engineered nucleation for memory, actuation, and optical technologies.