RAMAN, FT-IR AND DIELECTRIC STUDIES OF PZT-40 60 FILMS DEPOSITED BY MOD TECHNOLOGY/

Ferroelectric Pb(Zr0.4Ti0.6) O-3(.) (PZT 40/60) thin films with unifor m composition have been fabricated using the metallo-organic precursor compounds lead di-ethylhexanoate Pb(C7H15COO)(2), titanium di-methoxy -di-neodecanoate Ti(OCH3)(2)(C9H19COO)(2) and zirconium octoate Zr(C7H 15COO)(4). These metallo-organic precursors were stored for more than four years and are very stable in ambient conditions, compared to sol- gel solutions. The structural development of these films under differe nt annealing temperatures was systematically studied using X-ray diffr action, FT-IR spectroscopy and Raman scattering. The results show that the overlapping of (h00) and (001) peaks of the PZT 40/60 films in X- ray diffraction patterns, mainly due to the small grain sizes in films , makes it very difficult to distinguish individual diffraction peaks and to identify the phases. In FT-IR measurements, the intensity of Zr /TiO6 metal-oxygen octahedral vibrational modes becomes stronger with increasing annealing temperatures, while the FT-IR spectral peaks of v ibrations of the residual carbon ligands (COO-) finally disappear at h igh temperatures, showing that FT-IR spectroscopy is a good way to mon itor the growth of the perovskite phase in PZT 40/60 films. Raman meas urements undoubtedly reveal the Raman spectra of these PZT 40/60 films in the tetragonal phase field, demonstrating that Raman spectroscopy is an effective tool to identify structures, especially in the case of thin films having small grains. The values of high dielectric constan t and the total remanent polarization obtained by ferroelectric pulse measurements show that the PZT film is a suitable material for non-vol atile random access memory and dynamic random access memory applicatio ns.