Structure Stability of LaAlO₃ Thin Films on Si Substrates

A series of amorphous and single-crystalline LaAlO₃ (LAO) thin films are fabricated by laser molecular-beam epitaxy technique on Si substrates under various conditions of deposition. The structure stability of the LAO films annealed in high temperature and various ambients is studied by x-ray diffraction as well as high-resolution transmission electron microscopy. The results show that the epitaxial LAO films have very good stability, and the structures of amorphous LAO thin films depend strongly on the conditions of deposition and post-annealing. The results reveal that the formation of LAO
composition during the deposition is very important for the structure stability of LAO thin films.