Die elektrolytische abscheidung von Kupferüberzü gen aus pyrophosphatelektrolyten

Abstract

• 1.

  1. In copper pyrophosphate solutions in the range of pH 8 – 9, the copper electrode is reversible with respect to the free copper ions in the solution.

• 2.

  2. At the cathode, the formation of a passive layer and the stepwise-reduction of the anionic copper pyrophosphate complex are most important. These phenomena determine the high cathodic polarisation and the finegrained structure of electroplated copper.

• 3.

  3. The investigation of the electrochemical behaviour of an iron electrode in copper pyrophosphate plating solutions showed that the passive and active state of the electrode depends on the following: the concentrations of the principal components, the pH, and the presence of adducts in the solution. These factors must be taken into account for the production of adhering deposits in the electroplating of copper.

• 4.

  4. A copper pyrophosphate electrolyte for bright copper plating on steel is described.