The preparation of anisotropic conductive paste and its application in FOB interconnection

Abstract

PurposeThe purpose of this study is to investigate the reliability of flex-on-board (FOB) interconnection connected with an anisotropic conductive paste (ACP), which is prepared by dispersing nickel balls in the epoxy-curing system. Design/methodology/approachDifferential scanning calorimetry was used to evaluate the curing characteristics of the paste. And the contact resistances of bonding joints and 90o peel adhesion were tested before and after high temperature and high humidity test (85 degrees C, 85% humidity), thermal cycling (-45 degrees C similar to 125 degrees C, 30min/cycle) and pressure cooker test (PCT, 121 degrees C, 100% humidity 2 atm) to evaluate the flex on board (FOB) interconnection reliability. FindingsIt is found that FOB test vehicles have been successfully bonded by using ACP for the first time. And the ACP bonding joint of FOB has good reliability and can meet the requirements of FOB interconnection. Compared with conventional anisotropic conductive film (ACF), this ACP interconnection provides higher adhesion strength, higher joint current carrying capability and higher reliability performance and lower cost for FOB interconnection. Originality/valueACP is applied in the interconnection of FOB. It has the higher reliability performance and lower cost for than the conventional ACF.