Board level reliability assessment of consumer components for automotive use by simulation and sophisticated optical deformation analyses

The development of automotive electronics (AE) towards autonomous driving applications generates various challenges, in particular also on the reliable functionality. In various cases dedicated automotive grade components are lacking and consumer components have to be used instead, which hardly fulfil automotive standards. Some of the reliability challenges are therefore thermo-mechanical in nature. Some example issues, which are related to consumer electronics (CE) packaging, in particular MEMS-packaging, are given in the paper. Main focus is laid on the development of FE-simulation based evaluation methodologies accompanied by experimental characterization methods, in particular with regard to solder fatigue. It is shown that secondary effects such as, for example, intrinsic warpage of the component and of the circuit board, that are system related effects, can play an important role in AE application. A newly developed optical multi-sensor metrology method is presented for the thermo-mechanical deformation measurement of electronic components and systems for different size and resolution ranges. Thermally induced intrinsic warpage of circuit boards and components were analyzed both by means of the method. It was found that significant intrinsic deformations and warpages can occur and should be considered directly in AE system design and indirectly when evaluation stress risks, e.g. for solder fatigue.