Application of hybrid methods to analyse interface properties of packaging materials on miniaturized specimens

The development of highly integrated electronic packages leads to increasing numbers of materials combinations and bi-material interfaces within packages. For the development of robust packaged systems a fundamental knowledge of reliability relevant material parameters is needed. Delamination in packaged systems causes subsequent cracking, e.g. of the encapsulants, and ultimately the failure of the electronic components. The characterisation of materials used for packaged systems requires numerous test methods. The correct approach to the lifetime models for interface is to apply fracture mechanics. This paper presents developments in newly designed testing methods for the analysis of bulk and interface properties derived from miniaturized test samples. The objective is to thereby enable lifetime prediction for typical failure modes. The new testing methods allow the analysis of delamination toughness with respect to the mode mixity (loading ratio mode I/ mode II). These test methods allow a large mode-angle range to obtain the critical energy release rate G_c(Ψ) and high-throughput testing under different loading conditions (temperature, moisture). The image correlation technique was used for analysis of crack tip location at the interface. For the extraction of fracture parameters (e.g. energy release rate G_c(Ψ) or stress intensity factor SIF) from these tests a finite element simulation is utilized.