Study of ACF Bonding Technology in Flexible Display Module Packages

Anisotropic conductive film (ACF) has been used for more than 30 years in flat panel display (FPD) module package. In this paper, the technical trends and development of ACF are described. Among all of them, ACF material design for flexible substrate bonding is critical for the development of flexible display. According to different process flow of flexible AMOLED, flexible substrate bonding technologies can be classified as “PI/Glass” and “Film type” substrate bonding. That is to say the flexible substrate bonding process can be implemented before and after PI substrate separation from the original carrier glass substrate. Based on the current results, soft conductive particles of ACF are developed and chosen in the PI/Glass substrate bonding. For the film type substrate bonding, especially in IC bonding, the design of ACF is very important in avoiding the insufficient conductive particle deformation issue induced by the sink of plastic substrate. Here, we present a feasible and simple flexible substrate bonding technology to package driver IC, FPC or COF for flexible AMOLED application.