Thin films of ferroelectric PZT were deposited on substrates of platinum and sapphire by means of rf sputtering, where the source material employed is a stoichiometric mixture of PbO, ZrO
2, and TiO
2 powders, contributing to, enhanced simplification and reproducibility over the hitherto reported processes.
Relation between substrate temperature and crystal structure of the deposited films as well as the transition of crystal structure with heat treatment after film formation were investigated by X-ray diffraction.
Studies of dielectric constant, loss tangent, remanent polarization and coercive field versus film thickness have indicated that both the dielectric constant and loss tangent settled to a constant value of ε=800, tanδ=1.0%, while the value of remanent polarization became no less than 15μC/cm
2, and the coercive field grew to be more than 50 kV/cm in the vicinity and above a film thickness of about 2μm. Furthermore, heat treatment in an atmosphere of Ar-O
2 has shown an ε=400, tanδ=1.2% and remanent polarization of 10μC/cm
2 even at a film thickness of 0.5μm. Optical transmittance in the visible range observed is about 80%. for films deposited on sapphire. The studies also deal with electrical and optical characteristics versus film compositions analyzed by Auger Electron Spectroscopy.
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