Patterning of lead-zirconate-titanate thick-film structures by electrophoretic deposition from ethanol-based dispersions

We studied the thickness uniformity and homogeneity of lead-zirconate-titanate thick films on gold-coated alumina substrates obtained by constant-current electrophoretic deposition from ethanol-based suspensions with different conductivities. Based on the geometry of the experimental set-up, a finite-element model was constructed. The numerical analyses predicted a non-uniform current-density distribution on the electrodes, which was higher at the edges. We expected a thicker deposit at the edges, which was confirmed by measuring the cross-sectional profile of the as-deposited layer. The thickness non-uniformity was more pronounced for shorter deposition times and when performing the deposition from highly conductive suspensions. In the latter case the rate of deposition was decreased and the homogeneity of the deposits was increased, as evidenced by the scanning electron microscopy images. A homogeneous and uniform layer with a thickness of about 40 μm was prepared from the ethanol-based suspension with a conductivity of 20 μS/cm after 120 s.