Solder fatigue of Wafer Level package assemblies. Comparison with flip chip BGA’S

Author

Regard, Charles ; Gautier, Christian ; Frémont, Hélène ; Val, Alexandre ; Roullier, Frédéric ; Schwindenhammer, Patrice ; Poirier, Patrick

Author_Institution

NXP Semicond., Caen

fYear

2008

fDate

20-23 April 2008

Firstpage

1

Lastpage

6

Abstract

In this paper the solder fatigue of WLCSP (wafer level chip scale packages) assemblies is studied and a comparison with flip chip BGA is made. Previous works have already shown that for BGA, the most critical parameters are size, thickness, and underfill. We have evaluated both by thermal cycling and by simulations the effect of thickness and underfill in the WLCSP´s case. WLCSP devices with a size of 13mm2 were stressed up to 1500 cycles to emphasize the BGA like failures and evaluate the behavior of this new technology. We have demonstrated that the same failure mechanisms occur in BGA and in WLCSP. We also highlight the criticality of the WLCSP regarding industrial assembly process on board.

Keywords

ball grid arrays; solders; thermal analysis; wafer level packaging; ball grid array; failure mechanisms; flip chip BGAs; solder fatigue; thermal cycling; wafer level chip scale packages; Assembly; Chip scale packaging; Electronics packaging; Environmentally friendly manufacturing techniques; Fatigue; Flip chip; Lead; Semiconductor device packaging; Silicon; Wafer scale integration;

fLanguage

English

Publisher

ieee

Conference_Titel

Thermal, Mechanical and Multi-Physics Simulation and Experiments in Microelectronics and Micro-Systems, 2008. EuroSimE 2008. International Conference on

Conference_Location

Freiburg im Breisgau

Print_ISBN

978-1-4244-2127-5

Electronic_ISBN

978-1-4244-2128-2

Type

conf

DOI

10.1109/ESIME.2008.4525100

Filename

4525100