Progression of multilevel metallization beyond 0.35 microntechnology

摘要

The first true revolution in multilevel metal technology occurredin the transition from 1.O μm to 0.8 μm design rules. Thatreduction brought about two new and revolutionary innovations, namely Wfilled straight wall contacts and vias and chemical mechanicalplanarization (CMP). As these processes evolved to fit the requirementsof 0.5 and 0.35 μm rules, the search for increased performance isdriving a new revolution as linewidths shrink below 0.35 μm. Thistechnology leap encompasses both materials and process technologies. For0.25 μm and extending into the 0.18 μm generation, two newmaterials: low dielectric constant polymers and Cu metallization promiseto play a major role in performance enhancement albeit at the cost ofsignificantly more complex integration. In addition to new materials,the additional levels and increased interconnect density in conjunctionwith finer metal pitches, will also greatly challenge lithographic andetch capabilities. This paper addresses issues and approaches inintegrating a 0.25 μm multilevel metallization process module fromthe point of view of both new materials and new process technologies