Anodic dissolution of copper in dilute hydroxylamine solutions: application to electrochemical mechanical planarisation of copper

The effect of anodic polarisation on dissolution of copper in hydroxylamine based chemical systems has been studied using a quartz crystal microbalance technique to evaluate their use in electrochemical mechanical planarisation processes. Copper dissolution in hydroxylamine solution increases with respect to overpotential η and dissolution rates as high as 600 nm min^-1 have been obtained at an overpotential of 750 mV. The effectiveness of benzotriazole (BTA) in inhibiting copper dissolution in these chemistries was also tested. It was found that BTA is effective in inhibiting copper dissolution only at lower overpotentials (≤250 mV).