Abstract: A composition and method for stripping tin or tin-lead alloys, and any underlying copper-tin intermetallic, from a copper surface. The composition includes an aqueous solution of approximately 5-60% nitric acid by weight, approximately 0.5-30% ferric nitrate by weight, and a nitric acid stabilizer selected from the group consisting of an amino-triazole, an amino-isoxazole, and a linear amino sulfone in the form H.sub.2 N--SO.sub.2 --R, where R is any alkyl or benzene group, wherein the stabilizer is present at a concentration sufficient to inhibit exothermic conditions, emission of toxic NOx gas, and copper attack. A soluble source of halogen ion, such as hydrochloric acid, can be added to the composition to yield a uniform, reflective, bright pink copper appearance, and to further reduce sludge formation. In addition, sludge formation can be eliminated by adding a soluble source of sulfate ion (SO.sub.4.sup.-2) to the composition.

Abstract: A composition for reducing a copper oxide layer to metallic copper so as to facilitate bonding a resin to the metallic copper is disclosed. The composition is an aqueous reducing solution containing a cyclic borane compound. Examples of such cyclic borane compounds include those having nitrogen or sulfur as a ring-forming members, such as morpholine borane, piperidine borane, pyridine borane, piperazine borane, 2,6-Iutidine borane, 4-methylmorpholine borane, and 1,4-oxathiane borane, and also N,N-diethylaniline borane.

Abstract: A composition for reducing a copper oxide layer to metallic copper so as to facilitate bonding a resin to the metallic copper is disclosed. The composition is an aqueous reducing solution containing morpholine borane.