Interfacial fracture toughness measurements in microelectronic packages with different test setups on samples from production

Abstract

Interfacial delamination has become one of the most important reliability issues in the microelectronic industry, and therefore more and more focus is set on related research. Critical interface fracture data are rarely given in literature. These data sets are very important for subsequent proceedings like failure modeling, lifetime prediction and design evaluation associated with reliability. A fast measurement method could be very helpful for the qualification and evaluation of technologies and products. Usually measurements deal with artificial samples putting a lot of efforts to produce them as close as possible to the product containing the materials, surface treatments and fabrication conditions from the product. It is costly and time consuming to prepare production-like samples. We show the first version of a newly developed loading device, called micro Mixed Mode Tester (μMMT), for samples cut from real packages, which are production samples. This approach enables us to obtain critical fracture data of the lead frame interfaces in microelectronic packages. The interfaces we look at consist of the partners Cu-Lead frame (Cu) with epoxy-based Molding Compound (MC) or epoxy-based Glue-Die Attach (DA). The main advantage of using production samples is that the specimens contain all the impacts associated with the manufacturing and processing of the products. The newly developed method has the potential to become a standard test solution for interface toughness measurements, optimized with respect to analyzability, reproducibility, stability and total test cost and allows us to obtain more accurate values of the interfacial toughness. The evaluation of the critical data with respect to interfacial fracture mechanics needs experiments and simulations to be carried out in parallel. The focus of this work is set on the experimental data as the first step.