Stress Analysis Near the Welding Interface Edges of a QFP Structure under Thermal Loading
The purpose of this paper was to investigate the reason why the inter-face delaminations occurred in the QFP structure. The stress concentration was the key factor responsible for the microcrack occurrence. In order to figure out which factors affect the stress distribution, the materials attributes and the struc-tures dimension were considered. The finite element program ABAQUS6.9 together with the analytical solutions of singular stress fields was used to calcu-late the stresses near the interface edges. In conclusion, it appeared that strong mismatches of the thermal expansion coefficients and material elastic constants of the chip and PCB would lead to serious singular stresses at the interface edges. Stress intensity factor K and stress singularity order X were given, based on which failure criterions could be established to predict the potential interface delamination. It is suggested that the good design of packaging structure depends on proper material selection and dimension determination.
Electronic packaging QFP structure Interfacial thermal stresses Stress concentration.
Zhigang Huang Xuecheng Ping Pingan Liu
School of Mechatronics Engineering, East China Jiaotong University,Nanchang, Jiangxi Province, P.R. China, 330013
国际会议
南昌
英文
306-313
2010-10-22（万方平台首次上网日期，不代表论文的发表时间）