Investigation of dissolution inhibitors for electrochemical mechanical planarization of copper using beta-alanine as a complexing agent

Dissolution inhibition capabilities of benzotriazole (BTAH) and ammonium dodecyl sulfate (ADS) are investigated, in combination with β-alanine, as a complexing agent for applications in electrochemical mechanical planarization (ECMP) of copper. Cu electrodissolution is induced by linear sweep voltammetry (LSV), and Fourier transform electrochemical impedance spectroscopy (FT-EIS) is combined with LSV to examine the relative roles of the electrolyte additives in governing the surface reactions of Cu under voltage activated conditions of ECMP. The experiments focus on the electrochemical rather than mechanical component of ECMP, and are designed to probe both the individual and combined effects of BTAH and ADS on Cu electro-dissolution in the absence of abrasion.