Method for electroless deposition of phosphorus-containing metal films onto copper with palladium-free activation

摘要

The method for selective deposition of Co-W-P system films onto copper with palladium-free activation consists of creating hydrogen-rich complexes on the metal surface prior to deposition. More specifically, the method consists of creating the aforementioned complexes on the copper surfaces prior to electroless deposition of a Co-W-P system films. This is achieved by contacting the copper surface with reducing agents for a short period of time and under an elevated temperature. Such reducing agents comprise a hypophosphorous-acid-based or borane-based reducing agents such as dimethylamine borane. Hypophosphorous acid is preferred since it is more compatible with the electroless deposition solution.