Strength and fracture analysis of silicon-based components for embedding

Influence of deposited metal structures on the failure mechanisms of silicon-based components

“…4 The results we obtained clearly showed a difference in the characteristic strength and strength variability between specimens tested either with the metallised side under tension or the silicon side under tension (cf. Fig.…”

“…This causes the formation of a step-like feature in the poly-Si layer, whose curvature could act as a notch during biaxial loading of the chip, thus producing a stress concentration. 4 Further in the centre of the contact (not shown), the Al interconnect is directly connected to the top copper electrode (thickness ∼10 m). The thin grey line across layers in proximity of the curvature in the poly-Si layer is a FIB artefact.…”

“…3a). 4 A universal testing machine equipped with a 200 N load cell (Zwick Z010, Zwick/Roell, Ulm, Germany) was used to pre-stress the specimens with the B3B fixture. The fundamentals of the method and aspects of its application are already described in the literature.…”

“…0%, 30%, 70%, 90%) of the characteristic fracture load (P 0 ≈ 11.5 N), which was previously measured on a collection of 30 samples belonging to the same material, as reported in Ref. 4. Once the target value was reached, a dwelling time of one minute was set for each step.…”

“…The rather low Weibull modulus of the Si-side testifies a high scatter of the failure strength, and is in accord with values obtained in well-etched Si-wafer surfaces. 4,15,18,19 The purpose of the present work is to clarify the mechanisms that lead to fracture on the metallised side and extend the analysis to predict the failure mechanisms of Si-based multilayer components under biaxial loading. Focused Ion Beam (FIB) analyses are performed on pre-damaged specimens in order to detect the locations where the failure can initiate as well as the stress conditions in the damaged region.…”