Mechanical in-situ characterization of micro systems during encapsulation and integration processes in structural components

One of the present trends in microelectronic is the embedding of electronic devices directly into structural components. This integration of smart systems into hybrid and light weight structures also is a main objective of MERGE, the research cluster of excellence on Technologies for Multifunctional Lightweight Structures. The integrated silicon sensor system, also called stress monitor chip system (SMC), that allows health monitoring and failure detection in the hybrid structures is one of the MERGE demonstrators. It is capable of determining the magnitudes and the distribution of the mechanical load induced into electronics and sensor dies during embedding processes like encapsulation and moulding as well as afterwards in the service of the structural hybrid component. In the past years, the SMC system has already been shown to be highly accurate in stress monitoring during mechanical and thermal cyclic tests, in moisture swelling assessments and also during fabrication processes like transfer molding of Chip-on-Board (CoB) samples and epoxy underfilling of flip chip samples [1,2]. This paper investigates the individual process steps from the bare sensor chip up to the completion of the sensor integration in the lightweight structure regarding the induced mechanical stresses by using the SMC system.