Superstable, High-Conductivity Cu Conductive Adhesive

Materials with high conductivity and low cost are urgently required for electronic products, particularly copper conductive adhesives. Developing reliable copper conductive adhesives (ECAs) remains a great challenge due to their low conductivity and easy oxidation. In this article, copper microflakes with surface passivation by formate ions and thiols were used to create an antioxidant copper adhesive. We demonstrate that the surface modification has no impact on the electrical conductivities, even in salt spray, acid, alkaline, high temperature, and humidity conditions. After being cured at 250 °C for 30 min, the produced Cu ECAs displayed an ultralow resistivity of 65.12 μΩ·cm–1. Excellent stability enables its resistance to maintain a low level after 1000 h of aging at 200 °C and 85%RH 85 °C. This study establishes the enormous potential of Cu ECAs with antioxidants for low-cost microelectronics packaging.