Ferroelectric thick films on LTCC substrates - preliminary results

PZT (PbZr/sub 0.53/Ti/sub 0.47/O/sub 3/ with 6% of PbO and 2% of Pb/sub 5/Ge/sub 3/O/sub 11/) thick films with a low sintering temperature were printed and fired on either pre-fired or green LTCC foils (LTCC 951, Du Pont). The electrical characteristics of these PZT thick films, together with a set prepared on alumina substrates, were compared. The electrical characteristics of the samples fired at 800/spl deg/C deteriorated significantly due to interactions between the LTCC substrate and the PZT layer. It is presumed that the SiO/sub 2/ that diffused from the LTCC into the PZT layers formed low-permitivity lead-based silicates, which are detrimental to the dielectric properties of the PZT.