19.1: Invited Paper: Driver IC Packaging Technologies Using Anisotropic Conductive Films in Flat Panel Display

Abstract

AbstractAnisotropic conductive films (ACFs) are adhesive films with anisotropic conductivity induced by dispersing conducting particles such as metal coated plastic balls and metal particles into polymer matrices such as thermoplastics and thermosetting resins. ACFs have been widely used for driver IC packaging technologies in FPDs(Flat panel displays) such as LCDs(Liquid crystal displays) for last two decades. So far various packaging technologies such as TCP(Tape carrier package) on LCD panel or PWB(Printed wiring board), COF(Chip on flex) on LCD panel or PWB, and COG(Chip on Glass) using ACFs have been realized to meet the requirement of fine pitch capability and make the flat panel displays smaller, lighter and thinner. In this paper, the history of ACF and driver IC packaging are described. In addition, it is mentioned that how important driver IC packaging is in implementing the miniaturization, high resolution, low cost and high display quality. ACF material design for COF which is advantageous in fine pitch interconnection is described. It is indicated that low temperature curable ACF is very useful in improving productivity of LCD modules and reducing the thermal stress at the interface in large LCD modules. We also indicates that the warpage of LCD panel after COG interconnection induces the light linkage issue in LCD modules. Lowering bonding temperature of ACF is also very important in reducing the warpae issue and avoiding the light linkage issue when COG is applied for driver IC packaging in large LCD modules.