The effects of solvent on the properties of sol-gel derived PZT thin film

Pb(Zr,Ti)O/sub 3/ (PZT) thin films have been actively investigated for use in nonvolatile memory devices, piezoelectric sensors, pyroelectric infrared detectors and surface acoustic wave (SAW) devices etc. To fabricate PZT thin film, sol-gel method has been commonly used because of its several advantages such as ease of composition control, high purity, and low processing temperature. In sol-gel processing, it was reported that the solvent of stock solution strongly effects the final properties of PZT thin film. However, a solvent for stock solution is limited from the consideration of reaction with precursor. 2-methoxyethanol has been generally used due to its high reactivity. However, to improve the density of film, solvent with light molecular weight is more desirable. Even though the solvents with light molecular weight has the advantage, those have been rarely used as solvent because it is difficult to control the reaction kinetic between the solvent and precursor alkoxide. Due to the limitations mentioned above, there were few reports about the sol-gel derived PZT thin films using light alcohol such as methanol and ethanol. Moreover, comparing the effects of various solvents to final PZT films has never been reported. Therefore, in this work the authors study the effects of the solvent on the properties of PZT films.