Scaning probe tomography for advanced material characterization

With the introduction of three-dimensional (3D) devices and stackable architectures for both logic and memory applications, the physical characterization of 3D nano-sized volumes is becoming of paramount importance. Furthermore, for electronic devices the characterization cannot be limited to the topographical and compositional properties but it also has to enable the analysis of electrical properties of the sample. Therefore the main requirements for a valuable 3D characterization technique are: (1) nano-scale sensitivity for morphological and electrical features and (2) capability to probe in the three dimensions. In this work we propose an approach, termed scanning probe tomography, which is based on extending the 2D-analysis capabilities of SPM towards 3D thereby creating a valuable technique for three-dimensional characterization of ultra-scaled volumes. This is demonstrated through the analysis of the conductive filament in a conductive bridging memory device.