Investigation of Characteristics of the Capillary-driven Underfill Flow
Underfill is applied to fill the gap between the silicon chip and the organic substrate of the flip-chip to enhance its thermal-mechanical reliability.This paper focus on the traditional capillary-driven underfill process.Different capillary models including surface force model and volume force model,are verified with an experiment in predicting the movement of the melt-front.The characteristics of underfill flow are studied through 3D numerical analysis.Volume of fluid(VOF)method is used in tracking the melt-front of the underfill flow.The two models are calculated through a CFD code Ansys Fluent which is formulated with the finite volume method.It is found that the surface force model is more accurate in predicting the movement of the melt-front than the CSF model,which exaggerates the infiltration velocity of the underfill flow.An experiment has also been carried out to study how the melt-front advances with time.Complete filling for the PDMS specimen has been achieved with a commercial underfill material,and it is found that the underifill passage can accelerate the underfill flow.
Capillary-driven underfill Continuum surface force model PDMS material
Kanglun Wang Yan Wang Wenhui Zhu
State Key Laboratory of High Performance Complex Manufacturing,Central South University,Changsha 410083,China;School of Mechanical and Electrical Engineering,Central South University,Changsha 410083,China
国际会议
上海
英文
1070-1074
2018-08-08（万方平台首次上网日期，不代表论文的发表时间）