Basic Applications of Tungsten CMP

Similar to oxide CMP, a basic W CMP process uses a polisher equipped with a polishing pad, a cleaning unit, and a slurry distribution system. Owing to the need for an oxidizer, the slurry distribution system also includes a premixing sequence. As the lifetimes of these oxidizers are usually short, the 

FIGURE 9.1 Pourbaix diagram for tungsten calculated at 10 W04 (from 

FIGURE 9.2 Post-W deposition (basic contact layer stack diagram). 

FIGURE 9.3 Post W CMP, left two contacts show minor plug recession, right two contacts show minor plus protrusion. 

Tungsten CMP, to a lesser extent, has also been utilized to construct tungsten lines as a part of the interconnect via damascene or dual-damascene 

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