Preparation and characterization of PZT thick film enhanced by ZnO nanowhiskers for MEMS piezoelectric generators

A hybrid sol-gel route which was used to fabricate PZT thick film for MEMS piezoelectric generators was investigated. (100)-oriented Pb(Zr0.52Ti0.48)O3 thick films enhanced by ZnO nanowhiskers (ZnOw) were successfully prepared on Pt/Cr/SiO2/Si substrates via spin-coating ZnOw suspension and PZT sol. The influences of film thickness on the microstructure and electrical properties of composite thick film were investigated. XRD results show that PZT composite thick films have (100)-oriented perovskite structure. SEM results show that, the surface of as-prepared (100)-oriented PZT piezoelectric composite thick film is smooth, compact and crack-free, and the cross section is clear. The composite thick films exhibit good ferroelectric, dielectric and piezoelectric properties. 2 μm-thick (100)-oriented PZT piezoelectric composite thick film has the remnant polarization intensity and coercive field of 6.7 μC/cm2 and 92.5 kV/cm, the dielectric constant and dielectric dissipation of 1 431 and 0.44, respectively, and piezoelectric constant d33 is calculated to be 151.0 pC/N. The composite thick film is good to meet the use of MEMS piezoelectric generators.