Improved-reliability damascene interconnects and process of manufacture

An improved-reliability conductive damascene structure in a depression within an insulator layer of a semiconductor substrate and its process of manufacture. The process comprises depositing a wetting layer having a first metal in contact with the insulator layer in the depression, uniformly depositing a barrier layer over the wetting layer, and depositing a conductive layer having a second metal over the barrier layer. The conductive layer deposition step is performed at a temperature below which the first and second metals diffuse through the barrier layer to create intermetallic compounds of the first and second metals.