MICRO-RAMAN SPECTROSCOPY OF SOL GEL-DERIVED PB(ZRXTI1-X)O3 THIN-FILMS

Thin films of ferroelectric PbZrxTi1-xO3 were prepared by the sol-gel technique on sapphire and fused-quartz substrates with thicknesses ranging from 0.6 to 1.2 mum. Powders of the above substance were also prepared by hydrolysis and condensation of the same precursor sol and crystallized by holding them at 600-degrees-C for either 6 or 12 h. From a comparison of the Raman spectra it is obvious that both powders and the film on sapphire substrate belong to the perovskite structure, whereas the film on fused quartz has a phyrochlore structure. These observations agree well with x-ray measurements of diffraction patterns. Absence of 70 cm-1 E(TO) band in the film suggests that the film is rhombohedral with x being well above 0.535.