Research on copper pillars for 3D integration conducted with the support of Leti and the European Synchrotron Radiation Facility earned Alexandra Fraczkiewicz the Best Student Paper Award at the International Symposium for Testing and Failure Analysis (ISTFA) in California in December 2017.
The research demonstrated how tomography using X-rays emitted by a synchrotron source can be leveraged to analyze 3D integration defects with a limited number of projections, a suitable sample preparation scheme, and fully-automated post processing.
The innovative sample preparation scheme and highly coherent beam provided by the European Synchrotron Radiation Facility (ESRF) made it possible to observe nanometric voids (up to 30nm) and precipitations in copper pillars with non-destructive, high-resolution nanotomography. The characterization technique offers several benefits of interest to industry: First, the highly-coherent beam, which ensures high resolution in the final reconstruction of the original object; and, second, the ability to gather statistics from a large number of samples.
The research was made possible by the Platform for Advanced Characterization-Grenoble (PAC-G), created by IRT Nanoelec, which coordinated the cooperation between Leti and the ESRF.