Lattice-matched epitaxial ternary PrxY2-xO3 films on SrO-passivated Si (001): Interface engineering and crystallography tailoring

摘要

Rare earth bixbyite oxides (Re2O3) crystallize on Si (001) in 110-orientation due to either lattice mismatch or oxide/Si interface conditions. In this letter, a 1/2 monolayer (ML) SrO layer was employed as an interface engineering approach to achieve epitaxial ternary oxide PrxY2-xO3 (x = 0–2) films on Si (001) with a sharp oxide/Si (001) interface. The passivation layer is stable up to 780 °C. A fully lattice-matched Pr0.9Y1.1O3 film was obtained, which still has 110-orientation on Si (001). This allows us to clarify the decisive impact of the interface conditions-rather than lattice mismatch-on the growth orientation of Re2O3 films on Si (001).