Anumericalmethod forefficientfail uremodellingofth ree-dimensionalb ondpadstructures

AbstractThermo-mechanical reliability issues are major bottlenecksin the development of future microelectronic components. Thisis caused by the following technology and business trends: (1)increasing miniaturization, (2) introduction of new materials,(3) shorter time-to-market, (4) increasing design complexityand decreasing design margins, (5) shortened development andqualification times, (5) gap between technology and fundamen-tal knowledge development [1]. It is now well establishedthat for future CMOS-technologies (CMOS065 and beyond),low-k dielectric materials will be integrated in the back-endstructures [2]. However, bad thermal and mechanical integrityas well as weak interfacial adhesion result in major thermo-mechanical reliability issues. Especially the forces resultingfrom packaging related processes such as dicing, wire bond-ing, bumping and molding are critical and can easily inducecracking, delamination and chipping of the IC back-end struc-ture when no appropriate development is performed [3]. Thescope of this paper is on the development of numerical modelsthat are able to predict the failure sensitivity of complex three-dimensional microelectronic components while taking into ac-count the details at the local scale (i.e.,the back-end structure)by means of a multi-scale method. The damage sensitivityis calculated by means of an enhanced version of the previ-ously introduced Area Release Energy (ARE) criterion. Thisenhancement results in an efficient and accurate prediction ofthe energy release rate (ERR) at a selected bimaterial interfacein any location. Moreover, due to the two-scale approach, lo-cal details of the structure are readily taken into account. Inorder to evaluate the efficiency and accuracy of the proposedmethod, several two-dimensional and three-dimensional bench-marks will be simulated. Finally, the failure sensitivity of athree-dimensional back-end structure during a wire pull test isevaluated.1 IntroductionThe introduction of new low-