PZT and PT screen-printed thick films

Thick films (40-80 mum) of modified lead zirconate titanate (PZT) and lead titanate (PT) are screen-printed on alumina substrates electroded with Ag-P d. First the influence of the powder grain size distribution on film charac teristics after sintering is studied. With regard to the powder preparation , two processes are used: a mixed-oxide method and a wet coprecipitation pr ocess. Then thick films characteristics are compared with bulk ceramics one s. Two main factors explain the observed differences: residual porosity of the film and lateral clamping effect of the substrate. Other piezoelectric and elastic films coefficients are estimated from a plane wave model. (C) 2 001 Elsevier Science Ltd. All rights reserved.