Fast and Precise 3D Tomography of TSV by Using Xe Plasma FIB

3D tomography of TSVs was performed by combining Xe plasma FIB milling and lift-out techniques. This approach allows analyzing the structure of TSVs in detail using a method faster than the usual 3D tomography by Ga FIB and more precise than X-ray tomography. Both well-filled TSVs and TSVs with voids were analyzed and the results were compared. The analysis procedure was optimized in order to reduce the analysis time and to increase the throughput. The lift-out of the analyzed block of material was performed to obtain 90° angle between TSV and the ion beam axes, which is critical to reduce the curtaining effect and which allowed to increase FIB beam current significantly, reducing the analysis time.