To improve the mechanical compliance of a piezoelectric generator membrane, alterations in PZT processing including variations in crystallization temperature, cooling rates and precursor chemistry were made to reduce the residual stress. In addition to changing the stresses, these treatments also altered the morphology of the PZT and its modulus. Nanoindentation of these films were made to determine the moduli of the PZT films, which varied from 70GPa to 90GPa. The residual stress of 40:60 2-MOE PZT taken by x-ray diffraction were shown to reduce in residual stress from 210 MPa to 154 MPa with annealing. The static pressure-deflection of membranes with these films showed correlating composite effective stresses of 110MPa and 83MPa, Adding PEG to the precursor solution also lowered the stress of the PZT films. Bulge testing showed that decreasing the crystallization temperature from 700 ℃ to 600 ℃ lowered residual stress from 210 MPa to 154 MPa. Raman spectroscopy showed differences in both stress and structure of PZT deposited on thin support structures (2μm) over bulk wafers (350 μm). The compliance of the generators was also increased by etching Pt in highly stressed regions.
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