TEM and EDS investigation of heterogeneous interfaces in cofired multilayer ceramic capacitors

The interfacial microstructure and cofiring migration between Ag–Pd electrode and Pb-based relaxor ferroelectric ceramics were directly investigated via transmission electron microscope and energy dispersive X-ray spectroscopy (EDS). Different silver migration abilities of 70Ag–30Pd and 90Ag–10Pd electrodes were confirmed by EDS microanalysis. This difference is generally considered to be responsible for different effects of inside electrode on the reliability of multilayer cofired devices. Further, Pb diffusion and new phase formation near the interface were detected, incorporating interfacial microstructural observation. A good consistency of direct experimental evidence to the following theoretic analyses was well combined in this paper.