BILAYER METAL CAPPING LAYER FOR INTERCONNECT APPLICATIONS

摘要

The invention provides semiconductor interconnect structures that have improved reliability and technology extendibility. In the present invention, a second metallic capping layer (76) is located on a surface of a first metallic cap layer (60) which is, in turn, located on a surface of the conductive feature (58) embedded within a first dielectric material (54). Both the first and second metallic capping layers are located beneath an opening, e.g., a via opening, which is present within an overlying second dielectric material (68). The second metallic capping layer protects the first dielectric capping layer from being removed (either completely or partially) during subsequent processing steps. Interconnect structures including via gouging features as well as non-via gouging features are disclosed. The present invention provides methods of fabricating such semiconductor interconnect structures.