Electroless Deposition of Copper on Organic and Inorganic Substrates Using a Sn/Ag Catalyst

In this study, the electroless deposition of copper and silver was investigated on epoxy and silicon dioxide-based substrates. A cost-efficient, Sn/Ag catalyst was investigated as a replacement for the Sn/Pd catalyst currently used in board technology. The surface of the epoxy based polyhedral oligomeric silsesquioxane (POSS) films was modified by plasma and chemical etching for electroless activation without the creation of a roughened surface. The electroless copper deposited on the modified POSS surface exhibited excellent adhesion when annealed at 180 degrees C in nitrogen for 90 min or at room temperature for 24 hr. Electroless copper deposition was also demonstrated on oxidized silicon wafers for through silicon via sidewall deposition.