Diffusion barriers between noble metal electrodes and metallization layers, and integrated circuit and semiconductor devices comprising same

Abstract

A dynamic random access memory device (,) includes storage capacitors using a high dielectric constant material, such as, BaSrTiO,, SrBi,Ta,O,and PbZrTiO,, for the capacitors' insulator. The device includes a conductive plug (,) formed over and connecting with a semiconductor substrate (,). A buffer layer (,) of titanium silicide lays over the plug, and this layer serves to trap “dangling” bonds and to passivate the underlying surface. A first diffusion barrier layer (,), e.g., titanium aluminum nitride, covers the titanium silicide. A capacitor first electrode (,) lays over the diffusion barrier layer. The high dielectric constant material (,) is laid over the capacitor first electrode. A capacitor second electrode (,) is laid over the high dielectric constant material. A second diffusion barrier layer (,) is deposited on the capacitor second electrode. A conductor, such as aluminum (,), is laid over the second diffusion barrier layer. An isolation dielectric (,) can be deposited over the conductor at a high temperature without causing oxygen or metallic diffusion through the first and second diffusion barrier layers.