Low-Temperature Au–Au Bonding Using Nanoporous Au–Ag Sheets

In this study, we proposed low-temperature Au–Au bonding using nanoporous Au–Ag sheets, fabricated by dealloying a Au–Ag sheet in HNO3 solution, as a joint layer. The influence of the annealing temperature on the pore structure and chemical properties of the sheets was investigated. The chemical composition of the sheet was analyzed by X-ray photoelectron spectroscopy (XPS). It was found that the strength of Au–Au bonding with the nanoporous sheet increased. A sheet treated with liquid N2 was also tested; the strength of the Au–Au bond increased as a result of this low-temperature treatment.