Low Aspect Ratio Through-hole Filling by Copper Electroplating

摘要

Many factors effect Electro-copper plating of PCB (Printed Circuit Board) substrates, this plating determines through-hole for 3D electro-connection structures and brightness of surface. As technology developes, necessity of thin board, low aspect ratio through-hole filling will be studied. In this study, the parameters of three major items that additives, current density, and the stirring of plating chemicals inside the plating bath have been reviewed. It can be concluded that the input current methods and stirring have the greatest impact on filling of through-holes with low aspect ratio. However, when simply step up current and no-stirring conditions were used to increase the filling nature of plating, occurred void and irregular plating on the surface. In order to prevent voids and irregular plating, consider that concentration rate of PEG (polyethylene glycol) was increased from 10 ppm to 100 ppm.