Effects of the wet air on the properties of the lanthanum oxide and lanthanum aluminate films

Lanthanum oxide and lanthanum aluminate thin films were directly deposited on Si substrates by using metalorganic chemical-vapor deposition (MOCVD). The as-grown films were stored in wet ambient and dry ambient for days. The structural and the electrical properties of the films stored in two different ambient were examined in order to investigate the effects of the hydration reaction on the structural and the electrical properties of the films. As the storage time increased, the films stored in wet ambient showed some increases in physical thickness, surface roughness, equivalent oxide thickness and leakage current densities while the films stored in dry ambient did not. In addition, in case of the exposure to moisture, the lanthanum aluminate thin films showed better hydration resistance than the lanthanum oxide thin films.