SURFACE MORPHOLOGIES OF BATIO3 THIN-FILMS BY ATOMIC-FORCE MICROSCOPY

Surface morphologies of BaTiO3 thin films have been studied by atomic force microscopy (AFM). The films on (111)InSb, indium tin oxide (ITO) -coated glass and (100)Si substrates are deposited by in-situ metalorg anic chemical vapor deposition (MOCVD) at different deposition tempera tures of 300-degrees-C, 400-degrees-C and 600-degrees-C, respectively. AFM under ambient conditions showed that the BaTiO3 film deposited on the ITO-coated glass had a smooth surface consisting of large hemisph erical grains, while the film on (100)Si had a slightly rough surface with [110]textured rectangular grains. As-grown film on the (111)InSb substrate was in the amorphous phase except near the interface, result ing in a rough surface. Our results of dependence on the kind of subst rates and growth temperature suggest that the surface morphology of th e as-grown films is strongly influenced by the crystallinity and growi ng characteristic of the film. For low-temperature growth below the de position temperature of 600-degrees-C, surface roughness of the BaTiO3 film is strongly dependent on growth temperature rather than crystall inity of the films related to substrates.