Thermal cycling analysis of TAB OLB connection with ACF

This paper reports on the numerical prediction of the deformations and stresses in an anisotropic conductive film (ACF) for connection between the outer lead bonds (OLB) of a tape automated bonded (TAB) assembly and a glass panel. First, the ACF was bonded to the glass panel under heat and pressure and the whole assembly was cooled to room temperature. At this point, a very small residual stress existed. After that, the OLB of the TAB assembly, consisting of copper leads and a polyimide film, were bonded to the ACF. During the bonding process, large stress concentrations were found and the ACF experienced large deformations. The ACF and OLB finally merged together due to the heat and the pressure. This phenomenon is in good agreement with examinations of OLB using a scanning electron microscope. Similar to the pre-bonding process procedure, the assembly was allowed to cool to room temperature. The residual stress obtained was small. After the simulation of the manufacturing process above, thermal cycling from -25°C to 125°C was applied to the assembly. Von Mises stress distributions were obtained. The results provided useful information on the effects of thermal cycling on the TAB OLB with ACF