Investigation on reliability and failure analysis of plastic encapsulated microelectronics

Plastic encapsulated microelectronics used in a large variety of applications offer significant advantages in terms of cost, size, weight and product variety. However, PEMs are non-hermetic package and the plastic mold materials are inherently hygroscopic and absorptive, so the PEMs are permeability to moisture. Furthermore, the mismatch of coefficient of thermal expansion between the mould compound and various interfaces makes the PEMs more sensitive to thermo-mechanical stresses. In this paper the reliability issues of PEMs are investigated. And the related failure modes and failure mechanisms are summarized and illustrated by typical failure analysis cases. In the end, some precautions for minimize such failures are presented.