Pulse Potential Confined Electrochemical Polishing on Gallium Arsenide Wafer

Free of tool wear, residual stress, and surface damage, electrochemistry plays a significant role in precision machining. We report here semiconductor polishing technique based on electrochemically induced chemical etching, which the concentration distribution electrogenerated etchant between electrode workpiece can be precisely controlled by pulse frequency potential applied to electrode. A theoretical model is established, finite element analysis shows that difference at peak valley rough dependent pulse. Consequently, diffusion distance electrode/electrolyte interface effectively tuning potential. Under mechanical motion mode, roughness raw GaAs reduced efficiently from 700 nm 5.1 nm. This ideal for electrochemical wafers.