Tsutomu Kono

Study on prediction about residual position of void generated by resin flow

Liquid epoxy resin is used in various types of mobile information equipment and devices and expected to be a key material for flip chip packaging [1-2]. The flip chip connection process is a thermo-compression molding process. In this process, air voids may remain behind due to the bump shape and resin properties; therefore, an appropriate molding condition is necessary. We developed a computer-aided engineering (CAE) technique to calculate the generation of air voids and flow of resin and evaluated it in terms of prediction about the position of residual voids. This technique involves global resin-and-particle coupled moving and local air-resin two-phase flow analyses. In this paper, we give an example of prediction about the position of residual voids generated by resin flow by using our CAE technique. By clarifying the molding phenomena through analysis, we clarified the material properties suitable for a molding process.