Mechanism of Hypophosphite‐Reduced Electroless Copper Plating

Abstract

Effects of nickel deposit and boric acid of hypophosphite‐reduced electroless copper plating were studied by cyclic voltammetry. Nickel deposit can catalyze the oxidation of hypophosphite, and boric acid can enhance the reduction of nickel ion. In conjunction with the results of EPR studies of copper (II) complex ion and data of stability constants of copper (II) complex ion, it was found that the rate‐determining step in hypophosphite‐reduced electroless copper is the reduction of copper (II) complex ion and only those copper (II) complex ions that form dimeric structures have a significant plating rate.