Abstract
The electroplating module in the feature scale topography simulator EVOLVE is used to study the roles of plating additives. By comparing predicted Cu film profiles with experimental results, we can assess the adequacy of proposed chemistry models. In this paper, we focus on additives that act as leveling agents that can result in seam-free deposits fills through bottom up filling. In the plating model, we assume species transport by diffusion. The potential and concentrations are coupled through the current density at the electrode. The Cu deposition reaction is treated as a charge transfer reaction; Cu+ adsorbed onto the surface undergoes further reduction and becomes part of the growing film. The leveling agent is assumed to be in the mass-transfer limited regime. In our proposed chemistry model, the leveling agent is transformed to new species on the surface. Simulation results reproduce the effects observed in experiments.