Direct chip interconnect with adhesive conductor films

Feasibility study results on direct chip interconnection (DCI) using anisotropic conductive polymer material on both flexible and rigid substrates are discussed. The concept is to simultaneously attach and electrically interconnect IC chips to circuit traces. When conductors are joined under heat and pressure to form a bond, metallic spheres within the adhesive layer make contact with both surfaces but not each other, causing the anisotropic conductivity. Since process parameters (such as temperature, pressure, and cure time) as well as chip/substrate registration are equally critical to the success of making electrical interconnections, a real-time interconnect process monitor and methods to identify the root causes of interconnection failures during, and after, the bonding process were developed. The process monitor and the techniques used to verify the establishment of interconnections are elaborated