Mechanical analysis of wafer testing with FEM simulations

Research output: Contribution to journalResearch articleContributedpeer-review



In this work, finite element models are applied to analyze the influence of different parameters on crack failure probability during wafer testing. Regarding simulations, there are still very important aspects lacking in the existing literature. Very few publications take into account the plastic behavior of the metal layers of the structures. According to the results of this work, including plasticity in the simulations is essential to explain crack failure. Here we analyze how the applied force, mechanical properties and thickness of the layers are related to the deformation of the chip structure and the tensile stress in the oxide layer. Parametrizations are performed in order to find the main influences on crack failure. In a first approach, very simple models, which reproduce only pure elastic behavior, are considered. Subsequently, we present the results from more complex models, which reproduce the elastoplastic behavior of the metal layers. These simulation results are discussed and compared with experimental results from literature. Finally, conclusions and a prospective for future work are presented. A mesh and convergence analysis is included, in order to support the model results.


Original languageEnglish
Pages (from-to)166-182
Number of pages17
JournalMicroelectronics Reliability
Publication statusPublished - 1 Aug 2016