Electrophoretic deposition of lead-zirconate-titanate perovskite thick films with low sintering temperature

We have studied the processing of lead-zirconate-titanate PbZr0.53Ti0.47O3 (denoted PZT) based thick films using an electrophoretic deposition (EPD) process in order to obtain the active film with desired thickness and porosity at low the sintering temperature. The colloidal suspensions were prepared by mixing the ceramic powder in ethanol with the controlled addition of a polyelectrolyte salt and an organic base. In order to optimise the deposition process, the stability of the PZT and Pb5Ge3O11 (denoted PGO) particles in ethanol-based suspensions was studied. The electrophoretic deposition of PZT-PGO was performed from a mixture of optimal PZT and PGO suspensions in an appropriate molar ratio. PZT and PGO acting as a sintering aid were deposited on an Al2O3/Au substrate at a constant applied current and sintered at 850 degrees C. The thickness of the deposit was controlled by the deposition time and the applied current. PZT-PGO thick films deposited at 1.2 mA for 60 seconds and sintered at 850 degrees C for 8 hours exhibited a room-temperature dielectric permittivity of 1050, dielectric losses of 0.038, a remanent polarisation P-r of 29 mu C/cm(2), a coercive field E-c of 21 kV/cm and a d(33) of 97pC/N.