Microsolder ball incorporated nanofiber anisotropic conductive adhesives (microsolder/nanofiber ACAs)

We suggest and investigate a new concept of nanofiber ACA that incorporates microsolder balls into nanofiber to obtain stable three-dimensional electrical properties of fine pitch electronics. This adhesive offers many advantages, such as suppressing microsolder ball movement during resin flow, perfect X-Y axes insulation at 25 μm fine pitch, and easy fine solder ball handling. Microsolder balls can be successfully incorporated into a nanofiber structure through an electrospinning process, and they have good solderability within the nanofiber/epoxy matrix.