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Highlights • Copper pillars are imaged using 6 different 3D imaging techniques. • 3rd generation synchrotron beamlines and lab equipments are assessed. • A new sample preparation for synchrotron tomography is successfully tested. • The final volumes are compared, based on image quality and analysis time. Abstract In microelectronics, recently developed 3D integration offers the possibility to stack the dice or wafers vertically instead of putting their different parts next to one another, in order to save space. As this method becomes of greater interest, the need for 3D imaging techniques becomes higher. We here report a study about different 3D characterization techniques applied to copper pillars, which are used to stack different dice together. Destructive techniques such as FIB/SEM, FIB/FIB, and PFIB/PFIB slice and view protocols have been assessed, as well as non-destructive ones, such as laboratory-based and synchrotron-based computed tomographies. A comparison of those techniques in the specific case of copper pillars is given, taking into account the constraints linked to the microelectronics industry, mainly concerning resolution and sample throughput. Laboratory-based imaging techniques are shown to be relevant in the case of punctual analyses, while synchrotron based tomographies offer highly resolved volumes for larger batches of samples. [ABSTRACT FROM AUTHOR]

Highlights: [•] X-ray tomography in a SEM is efficient for 3D integration in microelectronics. [•] Employing thin metal targets as X-ray source increases the scanner resolution. [•] A 3D resolution pattern has been created by using a plasma FIB. [•] The 3D resolution of the instrument is proved to be about 500nm at 8.4keV. [Copyright &y& Elsevier]

Abstract: Different FIB-based sample preparation methods for atom probe analysis of transistors have been proposed and discussed. A special procedure, involving device deprocessing, has been used to analyze by APT a sub-30nm transistor extracted from a SRAM device. The analysis provides three dimensional compositions of Ni-silicide contact, metal gate and high-k oxide of the transistor gate. [Copyright &y& Elsevier]