Paper Title
Particle-Fluid Simulation of Flip Chip Capillary Under Fill Process Using Discrete Phase Model

Abstract
This paper investigates a capillary underfill flow in flip-chip encapsulation with the consideration of fillerparticles that is being dispersed in the epoxy resin to form underfill fluid. Two-ways coupled particle/fluid simulation have been implemented for the application of capillary underfill using discrete phase model (DPM). The flow front together with the instantaneous positions of filler particles and its velocity have been depicted at selected filling progression. The pressure contour and velocity streamlines of the underfill flow were computed and presented. The necessity of considering the particulate phase of filler particles in simulating the underfill process have been emphasized. While past numerical studies regard the underfill as single immiscible fluid upon neglecting the filler, current methodology would shed a new light in the future of underfill researches and optimization of filler technology. Indexed Terms―Capillary underfill,Discrete phase model (DPM),Flip-chip encapsulation