Abstract
Piezoelectric thick films of 0.85Pb(Zr,Ti)O_3 - 0.15Pb(Zn,Nb)O_3 (PZT-PZN) were fabricated on platinum-coated ZrO_2 substrates by conventional screen printing and were fired at 750-800℃. In addition to low-temperature sintering of PZT-PZN piezoelectric powder composed of active PZT synthesized by sol-gel method and low temperature calcination, the dispersion of paste components including PZT PZN powder and amorphous PbO-GeO_2 flux material made a densely-structured thick film by accelerated liquid phase sintering. In spite of the plane restriction of the platinum coated substrate during firing, the relative density of the thick films fired at 750-800℃ were 82-89%. As the relative density of the fired thick film increased, improved polarization properties were observed. Dense thick film fired at 800℃ showed remanent polarization of 17-18 μC/cm^2 and a coersive field of 13-14 kV/cm. Cantilevers made of these thick films presented a bending motion, making them useful as unimorph actuators.