A Study on the Corrosion Effects by Addition of Complexing Agent in the Copper CMP Process

Copper CMP in terms of the effect of slurry chemicals (oxidizer, corrosion inhibitor, complexing agent) on the process characteristics has been performed. Corrosion inhibitors, benzotriazole (BTA) and tolytriazol (TTA) were used to control the removal rate and avoid isotropic etching. When complexing agent is added with H$_2$O$_2$ 2 wt% in the slurry, the corrosion rate was presented very well. In the case of complexing agent, it was estimated that the proper concentration is 1 wt%, because the addition of tartaric acid to alumina slurry causes low pH and the slurry dispersion stability become unstable. There was not much change of the removal rate. It was assumed that BTA 0.05 wt% is suitable. Most of all, it was appeared that BTA is possible to be replaced by TTA. TTA was distinguished for the effect among complexing agents.