Interface formation and defect structures in epitaxial La ₂Zr₂O₇ thin films on (111) Si

The epitaxial growth, interface formation and defect structures in epitaxial La2Zr2O7 (LZO) thin films on (111) Silicon (Si) were analyzed. The LZO films were grown in a molecular-beam epitaxy chamber designed for oxide epitaxy. Structural characterization was conducted during growth using reflection high-energy electron diffraction (RHEED) and x-ray diffraction analysis. The pyrochlore and fluorite structures with same chemical composition were revealed by transmission electron microscopy (TEM). The results show that excess oxygen diffusion and interfacial silica formation were prevented by the structural complexity of the ordered pyrochlore structure.