Inter-diffusion phenomena and electrical conduction in thick-film segmented-resistor structures

Inter-facial processes and charge-transport mechanisms in a segmented resistor have been investigated using single- and double-layer resistive test structures. Microstructure studies of the cross section of the specimens supported by elemental mapping using energy- and wavelength-dispersive X-ray analysis show that, in dual-layer structures, RuO₂ agglomerates in a thin region near the interface and the current flow takes place principally through this region. From the Arrhenius plots of the specimens combined with Mott's T^1/4 law, it is found that the conduction mechanism at the junction of two cofired thick resistive films is governed by the mechanism of the lower-sheet-resistivity film.