MICROSTRUCTURAL DEVELOPMENTS AND DIELECTRIC-PROPERTIES OF RAPID THERMALLY PROCESSED PZT THIN-FILMS DERIVED BY METALLOORGANIC DECOMPOSITION

Microstructural developments and dielectric properties of lead zircona te titanate thin films (0.22 mu m) with the composition Pb(Zr0.53Ti0.4 7)O-3 were studied. The films were prepared by metallo-organic decompo sition (MOD) and rapid thermal processing (RTP) in the temperature ran ge 475-825 degrees C for 2 min in an oxygen gas flow with and without postannealing. An amorphous-pyrochlore-perovskite phase transformation is indicated at or below 525 degrees C RTP temperatures while a direc t amorphous-to-perovskite phase transformation is indicated at higher RTP temperatures. A decrease in grain size with increasing temperature is correlated with an increase in and dominance of nucleation of pero vskite sites. The best dielectric and fatigue properties were exhibite d by films processed in the temperature range 725-775 degrees C. Hyste resis loops tended toward squareness and polarization charges increase d with increased temperature, Furthermore, 45% of the initial charge r emained after 10(9) switching reversals. A degradation, however, was o bserved in both properties at higher temperatures.