Formation of LaAlO3 films on Si(100) substrates using molecular beam deposition

Lanthanum aluminate (LaAlO3) films were deposited on Si(100) substrates by a molecular beam deposition method with an electron beam gun and annealed typically in N2 atmosphere at 800 °C for 1 min. Reflection high-energy electron diffraction observation as well as x-ray diffraction analysis showed that the crystalline quality of the LaAlO3 films was amorphous, even after annealing at 800 °C. It was also found from x-ray fluorescence measurements that the ratio of La-to-Al for LaAlO3 films was almost 1:1. The dielectric constant of LaAlO3 films was estimated to be 20–25 and the leakage current density was improved by about eight orders of magnitude in maximum after the annealing process.