Hexagonal rare earth (R=Eu-Dy) manganites: XRD study of epitaxially stabilized films

摘要

Epitaxial thin films of RMnO_3 (R=Sm, Eu, Gd, Dy) were prepared using liquid injection MOCVD and studied by XRD. The formation of high-temperature hexagonal polymorphic structure of DyMnO_3 and non-existing-as-bulk hexagonal EuMnO_3, GdMnO_3 and SmMnO_3 (traces) was observed on ZrO_2(Y_2O_3) (111) substrates at 900℃ due to epitaxial stabilization. For the thickness exceeding the critical one the oriented stable perovskite form grew on the hexagonal phase. Parallel deposition on perovskite or non-coherent substrates gave only the stable perovskite phase, epitaxially grown in the former case or oriented in the latter.