Effect of TTA-K as Inhibitor On CU/RU/TAN Structure based Patterned Wafer CMP

The inhibitor added into the slurry during copper/barrier chemical mechanical planarization (CMP) plays a vital role in controlling the dishing and erosion of the patterned wafer. In this paper, a kind of corrosion inhibitor TTA-K was introduced in H2O2 based alkaline slurry. The experimental results showed that the addition of TTA-K can effectively reduce the removal rate (RR) and static etch rate (SER) of Cu. The results revealed that with the increase of TTA-K concentration, the passivation effect was enhanced. The dishing and erosion test results showed that the TTA - K can effectively reduce the depth of dishing and erosion with different line widths and spaces. Electrochemistry, XPS and SEM measurement was implemented to characterize the mechanism of TTA-K passivation.