Modified cofiring behaviors between PMN-PNN-PZT piezoelectric ceramics and PZT-doped 70Ag–30Pd alloy metallization

The cofiring behaviors between PMN-PNN-PZT piezoelectric ceramics and 70Ag–30Pd electrode paste were investigated in view of sintering densification behavior, thermal expansion coefficients (TEC) and interfacial physical integrity. The results showed that mismatched cofiring characteristics have greatly affected the reliability of multilayer piezoelectric ceramic devices. The application of a PZT additive to 70Ag–30Pd electrode technology has markedly improved the above-mentioned cofiring mismatch. Favorable cofiring behavior was obtained, including a reduced differential shrinkage and TEC and modified interfacial microstructure.