The Electrochemistry of Electroless Deposition of Copper

Abstract

A two‐chamber galvanic cell enabled the simultaneous study of both oxidation and reduction processes involved in electroless copper deposition. The standing electrode potentials as well as the coupled electrode potentials were measured in the catholyte (, , Rochelle salt) and in the anolyte (, , Rochelle salt). The current passing during coupling was dependent on coupling time, catholyte and anolyte compositions, and the activation of the anode. The order of the deposition process as calculated from the coupling current compared favorably with that obtained by direct weight measurements. Evan's diagrams were constructed and used to correlate electrode potential, coupling current, and the mixed potential with the rate of the electroless deposition process.