Role of FA/O II Complexing Agent and Bit on Dishing and Erosion Reduction During Cu Barrier CMP

In the process of chemical mechanical polishing (CMP), dishing and erosion are generated after Cu CMP, which will greatly impact the electrical characteristics of the device. In this paper, the synergistic effect of FA/O II complexing agent and 1,2-benzisothiazolin-3-one (BIT) on dishing and erosion were investiged. The CMP results showed that FA/O II complexing agent can effectively improve the removal rate of copper, but can inhibit the removal of TEOS. After the addition of BIT, the removal of copper was inhibited, but the removal rate of TEOS could be improved. The synergistic effect of FA/O II complexing agent and BIT can effectively improve the reduction of dishing and erosion. The remaining thickness of copper in the trencth (ETHK) can also be controlled.