Predicted stresses in die-carrier assemblies in "stretchable" electronics: is there an incentive for using a compliant bond?

A die-carrier assembly subjected to external tensile forces or to bending moments applied to the ``stretchable{''} carrier is considered. The main objective of the analysis is to develop simple, easy-to-use and physically meaningful predictive analytical ({''}mathematical{''}) models for the evaluation of the interfacial shearing (in the case of tensile forces) and peeling (in the case of bending moments) stresses in the bonding material, as well as of the normal stress acting in the cross-sections of the die. Another objective of the analysis is to find out if a compliant bond could provide a sufficient buffering effect, so that the stress in the die is reduced to the allowable level. Our calculations based on the developed models indicate that there exists indeed an incentive for using highly compliant bonds for lower stresses in ``stretchable{''} electronics. (C) 2011 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim