Interfacial development and microstructural imperfection of multilayer ceramic chips with Ag/Pd electrodes

The interfacial microstructure between Ag/Pd electrodes and PMN–PZN–PT relaxor ferroelectric ceramics in cofired multilayer ceramic devices was investigated by transmission electron microscopy and scanning electron microscopy. Disadvantageous interfacial defects, such as delaminations, warping, gas holes and exaggerated grain growth, were identified. In addition to the preparation process, the composition of the inner electrode paste and the sintering densification compatibility between the layers played important roles in the interfacial development. The relationship of the interfacial microstructure to the reliability of the device is discussed.