A study of powder size combinations for improving piezoelectric properties of PZT thick-film devices

This paper details investigations into the effects of different powder size ratios on the d33 coefficient of thick-film PZT layers. The two powders used were 5H type PZT supplied by Morgan Electro Ceramics Ltd. These were prepared using ball milling for the large particles, ~2µm, and attritor milling for the small particles, ~1µm. These powders were mixed with 10% by weight of Ferro CF7575 lead borosilicate glass and an appropriate quantity of ESL 400 solvent to formulate a screen printable paste. The results show the optimum powder combination obtained and a final formulation for a practical thick-film paste. The highest d33 value, 63.5pC/N, was obtained with the 4:1 ball to attritor powder by weight paste formulation