Quality and reliability of advanced microsystem packaging Fracture problems in microelectronic packaging - crack evaluation and crack avoidance

摘要

The expression "Fracture Electronics" has been used as a working term in the recent years to characterize the application of advanced fracture analysis in the field of microelectronics, electronic packaging and some other fields of microtechnology and microsystem technology as well. With growing miniaturization the "local" material properties and local temperature gradients exert a greater influence on the reliability of microsystems than in any macroscopic components. Various kinds of inhomogeneities, localized stresses and the related phenomena of thermal "misfit" effects have to be taken into account In contrary to the smaller products the chip size itself has become larger within the last years and it will become considerably larger in the near future, too. From this it already follows that the deformation and crack phenomena of chips and of chip packages will become increasingly important though the whole microsystem will become smaller. To apply most of the known fracture mechanics concepts for microcomponents with cracks or crack similar defects the knowledge of the displacement and stress state in the crack surrounding is required. That's, because the crack stability in case of mechanical or thermal load strongly depends on the energy balance in this region. So there is a great interest in advanced techniques to measure these local fields to study the microscopic deformation and damage processes.