Pyroelectricity of PZT-based thick-films

We studied the pyroelectric properties of lead titanate-zirconate (PZT)-based layers prepared with standard procedures of thick film technology (950 degrees C peak temperature) on alumina substrate and with buried interdigital electrodes. The investigation was aimed at setting adequate procedures, and at identifying sample configurations, for measuring the relevant pyroelectric quantities rather than to optimize the material pyroelectric performances. The results show that the pyroelectric coefficient of our porous layers (similar to 1.2 +/- 0.1 x 10(-4) C/m(2) K) is lower than that of ceramic (similar to 3.8 x 10(-4) C/m(2) K) and dense thick-films (similar to 2 x 10(-4) C/m(2) K) of comparable composition, but the thermal properties of our samples (low heat capacity and thermal conductivity) as well as the low relative dielectric constant result in figures of merit better than the corresponding values either for ceramic PZT or other pyroelectric materials (including TGS and LiTaO3). Hence, porous ferroelectric thick-films are good candidate for new pyroelectric devices. (C) 1999 Elsevier Science S.A. All rights reserved.