Chemical mechanical planarization treatment

Kin KT, Tang FIS, Chan SF, Raghavan S, Martinez S. Treatment of chemical-mechanical planarization wastes by electrocoagulation/electro-fenton method. IEEE Transactions on Semiconductor Manufacturing vol. 18, No. 2, May 2006. 

Kin, K.T., Tang, H.S., Chan, S.F., Raghavan, S., 2006. Treatment of chemical—mechanical planarization wastes by electrocoagulation/electro-Fenton method. IEEE Trans. Semicond. Manuf. 19 (2006), 208-215. 

This different behavior can be explained by considering that for a CE mechanism (the reasoning is similar for an EC one), C species is required by the chemical reaction whose equilibrium is distorted in the reaction layer (whose thickness in the simplified dkss treatment is <5r = jDj(k + 2)) and by the electrochemical reaction, which is limited by the diffusion layer (of thickness 8 = yfnDt). For a catalytic mechanism, C species is also required for both the chemical and the electrochemical reactions, but this last stage gives the same species B, which is demanded by the chemical reaction such that only in the reaction layer do the concentrations of species B and C take values significantly different from those of the bulk of the solution. In summary, the catalytic mechanism can reach a true steady-state current-potential response under planar diffusion because its perturbed zone is restricted to the reaction layer <5r, which is independent of time, whereas the distortion of CE (or EC) mechanism is extended until the diffusion layer 8, which depends on time, and a stationary current-potential response will not be reached under these conditions. 

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