Thermophoretic deposition of palladium aerosol nanoparticles for electroless micropatterning of copper

A method for catalytic activation was introduced by producing palladium aerosol nanoparticles via spark generation and then thermophoretically depositing the particles onto a flexible polyimide substrate through a hole in pattern mask, resulting in a line (24 mu m in width) and a square (136 mu m x 136 mu m) patterns. After annealing, the catalytically activated substrate was placed into a solution for electroless copper deposition. Finally, copper micropatterns of a line (35 mu m in width) and a square (165 mu m x 165 mu m) were formed only on the activated regions of the substrate. Both patterns had the height of 1.6 mu m. (C) 2008 Elsevier B.V. All rights reserved.