Multilevel planarized-trench-aluminum (PTA) interconnection using reflow sputtering and chemical mechanical polishing

A multilevel planarized-trench-aluminum (PTA) interconnection is developed using reflow sputtering and chemical mechanical polishing (CMP). This new PTA interconnection technology has the advantages both for a simple process using only Al reflow sputtering for simultaneous via and trench filling and subsequent CMP, and for high reliability in the interconnection due to the use of reflow sputtering. A double-level PTA interconnection demonstrates 4 times lower via resistance and 9 times longer electromigration lifetimes in both wiring and vias than conventional interconnections.<>