Microstructure and adhesion strength of copper substrate after oxidation with a newly developed chemical solution

In this study, the surface of copper packaging substrates was treated by two newly developed black oxidizing solutions, which contain no environmentally hazardous chemicals, and do not contaminate silver or gold structures on the substrate. Compared with the substrate treated by some commercially available oxidizing solutions, the new solutions can produce oxidized substrates with much fewer loose particles. The microstructure of the treated substrates was examined by SEM, XRD, XPS and Auger spectroscopy. The adhesion strength of the copper substrates treated with the commercial solutions and the newly developed ones were tested and compared. Substrate surface condition after oxidation was checked using SEM