Phase and microstructural evolution during the interaction between bismuthoxide films and Pt/Ti/SiO2/Si substrates

The interactions between metalogranically derived bismuth oxide films and P t/Ti/SiO2/Si substrates have been investigated in this study. The diffusion of bismuth species to the substrate and that of titanium species to the fi lm surface occur during the heating processes, and pluralistic Bi-Ti-O phas es are formed. With an increase in the heating temperature, the diffusion o f titanium species is enhanced, thereby forming the compounds with a high T i/Bi ratio in films. Based on analysis of SEM and AFM, the microstructure o f films are significantly varied by the diffusion of titanium species, whic h results in the formation of large grains on film surface and causes a sig nificant increase in roughness of films. The above results imply that the i nterface between bismuth-layered perovskite films and Pt/Ti/SiO2/Si substra tes would be influenced by the interdiffusion of bismuth and titanium speci es.