Numerical Simulation Based Observation on the Contact Line Jump in Flip-Chip Under fill Process
This paper devotes to numerically visualize the propagation of underfill flow through the bump array during the flip-chip under fill process. Finite volume method (FVM) based numerical scheme is employed to simulate the underfill flow in bump array. The simulated underfill flow profiles are in great consensus with experimental observations in previous literature. Contact line jump (CLJ) phenomenon of underfill flow is observed particularly at the entrance and exit of each row of bump. The CLJ at exit took longer to occur as compared to CLJ at entrance, constitute time interval of 0.70 s and 0.07 s respectively. Both the mechanism of CLJ and formation of micro-void are discussed.
Index Terms - Contact line jump (CLJ); Flip-chip; Finite volume method (FVM); Underfill