Micro structured electrode and method for monitoring wafer electroplating baths

A microstructured electrode coupled with an analytical method designed to simulate the actual conditions on the wafer and to measure critical parameters such as mass transfer of the active plating components, deposition rates of the copper in the plating bath solutions, and/or additive concentration is disclosed. Thus, an offline method for process control is provided. Additionally, the electrode and method can be incorporated into a copper interconnect bath tool or copper interconnect bath distribution system for online control of the process chemistry. The microstructured electrode design consists of a patterned electrode surface that simulates the dimensions of the interconnects and vias. The analytical method can be any type of method that allows diffusion or kinetic information to be obtained, such as electrochemical impedance, electrochemical noise, and other voltammetric or galvanostatic methods.