Adsorption-desorption study of benzotriazole in a phosphate-based electrolyte for Cu electrochemical mechanical planarization

作者：Lin Jeng Yu^*; West Alan C

来源：Electrochimica Acta, 2010, 55(7): 2325-2331.

DOI：10.1016/j.electacta.2009.11.104

• Electrochemical mechanical planarization
• Benzotriazole
• Adsorption
• Desorption
• Microfluidic device

In this article, the adsorption-desorption behavior of benzotriazole (BTA) in a phosphate-based electrolyte developed for Cu electrochemical mechanical planarization (ECMP) is studied. The formation of a continuous BTA passive film adsorbed on the Cu surface has been characterized by atomic force microscopy (AFM). Additionally, the adsorption behavior of BTA was found to be mass-transfer-control led at lower operating potentials (<= 0.7 V vs. Ag/AgCl). Using a microfluidic electrochemical device and electrochemical impedance spectrum (EIS), it was also observed that at low BTA concentrations (<= 0.002 M), more time was necessary to form an effective passive film on the Cu surface. Furthermore, the desorption time obtained from a potentiometric response to the removal of BTA from the electrolyte increases with increasing BTA concentration or decreasing applied potential. It is critical to expand the operating potential window and to reduce the usage of inhibitors in the proposed ECMP process to enhance the removal rate and the reduction of organic residues.

• 出版日期2010-2-28