The best combination of aluminum and copper interconnects for a high performance 0.18 /spl mu/m CMOS logic device

A high performance 0.18 /spl mu/m CMOS logic device has been developed with 0.15 /spl mu/m transistors and six-level interconnects. The multi-level interconnect system consists of a conventional process with Al wire and a dual damascene process with Cu wire. 4-level Al interconnects with fine metal pitch are suitable for short distance wiring such as intra block cell to cell interconnects, whereas 2-level Cu interconnects with coarse metal pitch are used for long distance wiring such as mega block to block interconnects to achieve high-speed and high-density LSI devices.