Gallium-Indium-Tin Liquid Metal Nanodroplet-Based Anisotropic Conductive Adhesives for Flexible Integrated Electronics

Compared with traditional solder joint bonding, an anisotropic conductive adhesive (ACA) provides an efficient and simple method for the interconnection of small-scale electronics. The wider application of ACAs for nanoelectronics is still suppressed, however, by the lack of durable and cost-effective conductive components. Herein, a series of core-shell eutectic gallium-indium-tin liquid metal (LM) nanodroplets (NDs) with different diameters have been successfully synthesized and regulated by a combination of laser irradiation and sonication. Due to their high conductivity and good fluidity, these LM NDs were used as soft conductive filler micro/nanoparticles for fabricating ACAs. The as-prepared ND-based ACAs present satisfactory anisotropic conductivity when used to interconnect small-scale electronic circuits. Highly durable anisotropic electrical performance was also maintained in flexible packed devices, even under bending or twisting operation modes.