Relationship Between Molecular Structure and Removal Rates during Chemical Mechanical Planarization: Comparison of Benzotriazole and 1,2,4-Triazole

We examined the effect of the structure of corrosion inhibitors benzotriazole (BTA) and 1,2,4-triazole (TAZ) on the Cu removal rate during chemical mechanical planarization. Removal rates were higher for solutions containing TAZ than solutions containing BTA. Corrosion inhibitor films were characterized using atomic force microscopy, cyclic voltammetry, impedance spectroscopy, surface-enhanced Raman spectroscopy, and mass spectrometry. Inhibitor films formed from TAZ were thicker, more permeable, and rougher than films formed from BTA. The addition of glycine to the corrosion inhibitor containing solutions showed an increase in corrosion for the TAZ-covered Cu surface, little change for the BTA-covered surface, and an increase in removal rate for both systems. This study correlates removal rate with the physical properties of these two different corrosion inhibitors.