Reverse Damascene Process

A method for forming a metallization layer, comprising:

• depositing an under metal metallurgy (UMM) layer over a surface of a semiconductor substrate;
• growing a single metal layer from the UMM layer, wherein the single metal layer is grown from the UMM layer in a single processing step, which is uninterrupted by other processing steps;
• forming a patterned photoresist layer above the UMM layer having one or more cavities extending from a top to a bottom of the patterned photoresist layer;
• selectively etching the single metal layer and the UMM layer in areas not masked by the patterned photoresist layer to form metal layer structures shaped by the one or more cavities in the patterned photoresist layer;
• removing the patterned photoresist layer from the semiconductor substrate to leave the metal layer structures over the surface of the semiconductor substrate;
• forming a diffusion barrier layer that conforms to top and side surfaces of the metal layer structures;
• and
• forming an inter-level dielectric material onto the surface of the semiconductor substrate to fill areas between the metal layer structures.