New electroforming technology pressure aid for LIGA process

A new microelectroforming technique using air-pressure assistance in the electrolyte is introduced. The related theories and experiments are reported in this paper. The pressurized electrolyte reduces hydrogen bubble formation and defect on the substrate surface. The high pressure electrolyte limits bubble formation in electroforming. It also produces good throwing power from the experimental sample observations. The edges of the electroformed workpiece using the pressurized method were smoother than those produced using conventional electroforming. The metallurgical grains were finer when higher pressures were applied in the electrolyte based on SEM micrographs. Pressurized electroforming can increase the allowable current density, which can shorten plating time in the LIGA process. The high growth rate due to large applied current density results in large electroforming microstructure grains. The surface morphology of pressurized electroformed samples were improved compared with the conventional method.