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Surface Mounted Devices (SMDs) are widely spread throughout microelectronics and power electronics. They mostly employ epoxy molding compound (EMC) based encapsulations. Thus, enhanced lifetime assessment methods are necessary. To understand the stress situation in SMDs at the end of the production cycle, an improved model approach for the curing of EMC is implemented within Finite Element Analysis (FEA) simulations. During production in e.g a RTM process, material properties are spatially varying due to different curing degrees. Hence, a mismatch of mechanical properties is present, which in return leads to internal stresses. The introduced model approach is an extension to the work of Gschwandl. et al [1] and includes a stress-free deformation before vitrification, changing material properties during curing as well as plastic deformations and visco-elastic effects. The implementation in numerical FEA simulations allows for a better understanding of arising residual stresses and help optimizing the production cycle of SMDs.

The rapid expansion of the Internet of Things (IoT) and consumer electronics is driving the demand for microelectromechanical systems (MEMS) in the area of wearables, smartphones, and home and building applications. MEMS sensor packages feature a variety of polymeric materials which can significantly affect their behavior under environmental loads as humidity or temperature. A broad range of different polymeric materials can be applied in the packages, but to get a good MEMS sensor performance, an optimized application tailored material combination should be applied. To analyze the effect of the applied material types an advanced simulation approach has to be considered. A hygro-thermo-mechanical simulation based on measured temperature and moisture dependent material properties is presented. As MEMS sensor packages are complex multimaterial systems, the main challenge is the modeling of the moisture discontinuities in the interfaces. The discontinuity of moisture concentration has been solved by using the solubility approach.

Microelectromechanical systems (MEMS) and MEMS packaging solutions are gaining increased interests for electronic applications. These packages feature a variety of polymeric materials and composites e.g. fiber reinforced polymer laminates, insulating and conductive adhesives. Due to the sensitivity of MEMS devices to mechanical stress and environmental factors such as temperature and humidity, the influence of these factors on the device’s performance needs to be accounted for. In this contribution, a fabric woven glass fiber reinforced epoxy resin (BT epoxy resin) and two chosen adhesives commonly used in semiconductor and MEMS packaging have been considered and their dependency on environmental parameters have been studied with different testing methods. Based on the measured material properties a simulation process predicting the package under defined environmental loads is presented.