Effect of annealing conditions on alkoxy-derived PZT thin films. Microstructural and CV study

Abstract

Polycrystalline Pb(Zr_0.48Ti_0.52)O₃ thin films with the thickness of 0.2 μm on Pt-coated silicon substrates have been prepared by sol-gel process using electrochemically prepared titanium and zirconium solutions in methoxyethanol. Structure, morphology, and electrical properties of the films annealed by usual isothermal annealing for 1 hour and by rapid thermal annealing (RTA) for 1 minute have been studied. In contrast to isothermal annealing RTA results in highly oriented (100) films. This leads to higher dielectric constant (more than twice) of RTA annealed films, but no correlation between degree of orientation and polarization have been observed. Special attention has been paid to capacitance-voltage (CV) characteristics. Some parameters and simple models were introduced for the interpretation of CV data. Thus asymmetry of CV curves indicates that for the films prepared by RTA there exists a problem of disturbed layer formation at the Pt-PZT interface.