Characterization of the growth of sol-gel derived Ba---Ti---O thin films by laser Raman spectroscopy

The isothermal growth kinetics of sol-gel derived BaTi₅O₁₁ thin films has been studied by laser Raman spectroscopy. Thin films of the precursors were spin coated on silicon wafers with platinum or gold overlayers. The films were then annealed isothermally, and Raman spectra were recorded in situ. The time-dependent intensity changes of the Raman bands could be analyzed in terms of Avrami models. The interaction of the BaTi₅O₁₁ film with the platinum or gold overlayers during heat treatment apparently increased the Raman intensity by a factor of about 100.