Modeling of Acid Copper Anisotropic Deposition Based on Detailed Calculation of the Electrolyte Composition

Abstract

A multi-ion deposition model, based on constant applied voltage, was used to calculate the current distribution for anisotropic deposition in electrolyte composed of CuSO4 and H2SO4. The bulk species concentration was calculated by Pitzer’s model, including consideration of partially dissociated CuSO4false(normalaqfalse) and HSO4−. It was found, in some cases with high H2SO4 concentration, that the dissociation of CuSO4false(normalaqfalse) was higher than in the pure CuSO4 solution because of excess H+ ions. Further deposition modeling shows that H2SO4 and CuSO4 play different roles in anisotropic deposition. High H2SO4 concentration improves deposition uniformity but suppresses the filling ability. However, CuSO4 plays a role inverse to that of H2SO4. A moderate electrolyte composition for anisotropic deposition is thus suggested to be 0.1-0.3 M CuSO4 and 0.6-1 M H2SO4. © 2002 The Electrochemical Society. All rights reserved.

Numerical Simulation of Hydrodynamic and Mass-Transport Properties at a Laminar Rotating Cylinder Electrode

“…The Sherwood number associated with the four experiments was calculated according with Sh Cu,exp = j exp d 1 /͑nFC Cu,bulk D Cu ͒, where C Cu,bulk is supposed equal to 0.567 M according with the total copper sulfate dissolution assumption. This assumption is realistic in the present work conditions, as shown in the modeling work of Wu et al 25 The comparison between experimental results and numerical results exhibit bad agreement because of the importance of the natural free convection compared to the forced convection. 26,27 The forced convection appears to be smaller than the natural free convection with an importance ratio j forced /j total between 1/3 and 1/2.…”

Modeling and Experimental Validation of Electroplating Deposit Distributions from Copper Sulfate Solutions

“…Modeling and simulations can be cost effective ways of predicting the behavior of an electroplating system, and much work has been done to develop various models and software packages for simulations. Many mathematical models have been developed to describe an electrolyte's current distribution; however, the models are usually restricted to specific simplified geometries such as flat panels, rotating discs, or triangular geometries (1)(2)(3). Commercially available software packages have been developed that can make modeling complex geometries possible.…”

EIS and statistical analysis of copper electrodeposition accounting for multi-component transport and reactions

“…Based on the solution thermodynamics of the system, the following dissolved species are considered: Cu 2+ (species 1), H + (species 2), SO 2À 4 (species 3), cupric sulfate ion-pair CuSO 4(aq) (species 4) and bisulfate ion HSO À 4 (species 5) [39]. Thus, the following two homogeneous reactions and their respective equilibrium conditions are also incorporated into the model:…”