Materials science and integration bases for fabrication of (Ba _xSr_1-x)TiO₃ thin film capacitors with layered Cu-based electrodes

An investigation on the synthesis and material properties of layered TiAl/Cu/Ta electrodes was performed to achieve the integration of Cu electrodes. The TiAl layer provided an excellent barrier against oxygen diffusion into the Cu layer to inhibit Cu oxidation while the Ta layer is an excellent diffusion barrier to inhibit deleterious Cu diffusion into the Si substrate. Using the surface analytical methods, characterization of the Cu-based layered structure showed that two amorphous oxide layers were formed on both sides of the TiAl barrier.