Mechanism of 1,2,4-Triazole during Copper Chemical Mechanical Planarization

Based on the static corrosion tests and Arrhenius equation, the inhibition efficiency and adsorption mechanism of 1,2,4-triazole were studied. Besides, the effect of 1,2,4-triazole on the activation energy of wafer surface was analyzed. Combining with chemical mechanical planarization (CMP) experiments, the effect of BTA and 1,2,4-triazole on material removal rate during CMP process was investigated. It is found that the two inhibition mechanisms of 1,2,4-triazole involved, i.e. the formation of physisorption or chemisorption layer on the surface and the formation of a polymeric film of Cu(1,2,4-TA)₂. The reduction amount of activation energy during CMP was independent on the concentration of 1,2,4-triazole in slurry. The reduction amount of activation energy during CMP using slurry containing 1,2,4-triazole was larger than that using slurry with BTA, which indicated stronger mechanically induced chemical effect. The results are useful for optimizing component of the CMP slurry.