The development of lead zirconate titanate (PZT) films can be a fairly troublesome process when trying to obtain a viable thick crack-free film. Traditional methods for film fabrication via a pure sol-gel solution provide the best results, but still can have many problems. This paper maps out the specific spin-coating and annealing steps used in order to achieve a PZT film with minimal-to-no cracking and/or delamination. A seed layer of PbTiO3 (PT) was used in order to create nucleation sites for the subsequent PZT layers, virtually eliminating any delamination. All layers, including the PT base layer, were spin-coated at 3000 rpm onto a 100-mm silicon wafer (previously sputtered with Ti and Pt for adhesive and conductive purposes, respectively) and soft-baked at 150 °C for 10 min. Initial annealing procedures produced severe cracking, a result of the relatively high cooling rates through the Curie temperature (∼350 °C). The annealing process was refined, for individual layers, to 550°C for 120 s, with a cooling rate of 0.042 °/s between 400 and 300 °C. Final annealing was conducted at 600 °C for 30 min, with a cooling rate of 0.028 °/s between 400 and 300 °C. The resulting PZT layer was virtually crack-free. Platinum was sputtered again subsequent to PZT deposition in order to pole the piezoelectric material. A PZT/nanoparticle powder mixture was also investigated as the piezoelectric layer. PZT nanoparticles were suspended in the sol-gel precursor solution and then spin-coated also at 3000 rpm onto a 100-mm wafer and soft-baked at 150 °C for 10 min. The relatively slow cooling rate was extended between 500 and 100 °C in order to prevent any cracking that might occur along grain boundaries between the individual PZT nanoparticles. The resulting film was crack-free, however displaying areas of agglomerated nanoparticles.

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