Characterization of sol-gel Pb(Zr0.53Ti0.47)O3 films in the thickness range 0.25-10 μm

Films of nominal composition Pb(Zr0.53Ti0.47)O-3 (PZT) in the thickness range 0.25-10 mu m have been fabricated on Pt/Ti/SiO2/Si substrates using a propanediol-based sol-gel route. The spun-on coatings were prefired at 350 and 600 degrees C between successive deposition before firing the multilayer stack at 700 degrees C for 15 min. The variation crystallite orientation, microstructure, and dielectric and ferroelectric properties were determined as a function of film thickness. For a constant applied field of 150 kV cm(-1), remanent polarization decreased progressively from 35 to 17 mu C cm(-2) as film thickness decreased in the range 10-0.25 mu m; values of coercive field were reasonably constant, 18-19 kV cm(-1), for films between 2 and 10 mu m, but increased sharply below 2 mu m, reaching 46 kV cm(-1) for a 0.25 mu m film. Relative permittivity (epsilon(r)) decreased from approximately 1400 to approximately 940 with most of the reduction occurring in films less than 2 mu m in thickness. These trends are discussed in terms of the presumed influence of interfacial phenomena on the measured electrical response.