Abstract: The electrical performance of the stacked glass-ceramic capacitors depends largely on the inner electrode structure and the interface quality. In this work, several metal films, such as Pt, Au, Cu and Ag, were deposited by DC magnetron sputtering serving as inner electrode layers between the dielectric layer and the silver paste electrode of glass-ceramic capacitors. The effect of the deposited metal films on the electrical properties of Na₂O-PbO-Nb₂O₅-SiO₂ glass-ceramic capacitors was investigated. Compared with the single paste electrode structure, Pt and Au metal films could effectively improve the electrical performance of the capacitors, corresponding to an increase of equivalent capacitance by 25% and a decrease of leakage current by an order of magnitude. SEM observations indicate that the Pt, Au and Cu metal films would help the formation of a dense electrode/dielectric interface and inhibit the diffusion of silver, whereas a porous interface and intense silver diffusion are often found in the single screen-printed paste electrode and the deposited Ag metal electrode. The above results reveal that Pt and Au metal films as inner electrodes could make the interface microstructure inhibit the silver diffusion and enhance the overall performance of the glass-ceramic based capacitors.

Key words: metal film, inner electrode, glass ceramic capacitors, electrical properties, diffusion