Three-additive model of superfilling of copper

A model describing the effect of an accelerator bis(3-sulfopropyl)disulfide (SPS) and the two inhibitors poly(ethylene glycol) and Janus Green B (PEG and JGB) on the leveling efficacy on submicrometer trenches of an acid-copper plating bath ir described, simulated, and compared to experimental fill studies. All parameters of the model are estimated from electrochemical measurements on a nonpatterned, rotating disk electrode. A multicomponent version of a Frumkin isotherm is employed to account fur the interaction between SPS and PEG, and the interaction between PEG and JOB are described by a competitive adsorption. Langmuir model. Shape-change simulations employing these descriptions of the surface phenomena are consistent with fill studies over a large range of SPS and JGB concentrations; however, simulations do not predict the result that void-free deposits are achieved when the concentration of JGB is zero. (C) 2001 The Electrochemical Society. [DOI: 10.1149/1.1377898] All rights reserved.