Layered thin-film growth method for accurate stabilization of Ruddlesden-Popper phases & polymorphs
Author: Davidson, Bruce
Affiliation: UBC/Quantum Matter Institute
Type: Poster
Display Dates: 20.07.2026 - 21.07.2026
Board: MT-020
Thin film growth of complex oxides with the Ruddlesden-Popper structural motif, (AO)×An+1BnO3n+1 with integer n, represents a paradigm of calibration accuracy for several reasons. First, typically the parent perovskite ABO3 phase is structurally stable for a wide range of cation and oxygen off-stoichiometries so that deviation from the ratio A:B = 1 is often difficult to quantify. Second, strict monolayer doses are required when the structure is intentionally layered; this corresponds to supplying x = 1.00 in AxBx during growth of the perovskite block, or the resultant film will mix phases with different n. We employ an entirely in situ method based on electron diffraction to precisely determine absolute fluxes that allows the stabilization of phase-pure films, and determine the correspondence between the shuttering sequence and the resulting layered structure. This method allows precise stabilization of the pure n = 1 to 3 phases of titanate, nickelate and manganite phases, as well as half-integer n = 1.5 and 2.5 phases not available in bulk, as seen by electron diffraction, X-ray diffraction and electron microscopy. Structural fidelity requires interpreting the dynamic layer inversion mechanism that must be included in the layering schemes, both in the initial layers of growth as well as for layer-specific doping.