An experimental study of degradation of anisotropic conductive adhesive joints

The epoxy-based anisotropic conductive film (ACF) joints have the potential of being exposed to a hygrothermal environment and susceptible to moisture sorption. The long-term hygrothermal aging will induce the irreversible damages of epoxy resins system due to susceptibility of the polymer to hydrolysis, oxidation, etc. In this study, the hygrothermal environment test (85degC/85%RH) was used as an accelerator for the degradation of ACF joints in chip-on-glass (COG) assemblies. The effects of hydrothermal aging on the epoxy-based ACF joints were analyzed by Fourier transform infrared spectroscopy (FTIR) and scanning electron microscope (SEM). Results show that the changes of molecular conformations for the aged ACF have been found, and the fracture mechanisms of ACF joints have been gradually changed with the hygrothermal aging