New microelectrodes for the investigation ofthe electroforming of liga microstructures

Abstract

Mass transport is of critical importance during electroforming of LIGA microstructures, sincedifferent concentration profiles result in gaps of different lateral sizes. Two specially designed microelectrodeswere manufactured and demonstrated to be suitable for the systematic investigation of the masstransport during electroforming in microstructures. The Rotating Microstructure Electrode ( rme) facilitatesinvestigations under well defined hydrodynamic conditions. Limiting current densities were measuredin a redox electrolyte with Rotating Microstructure Electrodes and compared to results of a discelectrode rotating at the same rates. The Microstructure pH Electrode ( mpe) allows pH values to bemeasured near the cathode in microstructures, within the diffusion layer, during nickel electroplating. Theslope of the resulting pH gradient decreases with the growth of the deposit.