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edfas.org 31 ELECTRONIC DEV ICE FA I LURE ANALYSIS | VOLUME 24 NO . 3 evolution of the measured resistance as a function of the V DC is represented in Fig. 6c for three locations: the DTI, the p-type substrate, and themetal contact (locations are reported in themapping). For the DTI, as a function of the V DC , a symmetric evolution is measured. For the substrate and contact, a rectifying behavior, with smaller reverse currents attest the Schottky response of the SSRM nano- contact. Interestingly, SSRM reveals the FEOL structure but also gives information on the contacts of the back end of line (BEOL). For the mappings (Fig. 6c), for all V DC , all layers are visible, but the value of themeasured resistance evolves. For example, themeasured value of the contact is 10 6 Ω at -3V and 108 Ω at 3V. This analysis shows that it is crucial to specify theappliedvoltagewhen local properties are deduced. Complementary to SCM, SSRM shows that the DTI are completely electrically isolated with respect to the substrate. CONCLUSION This article presents experimental results obtained by SCM and SSRM based on an AFMwith amultidimensional approach. The crucial role of the applied V DC for reliable analysis is highlighted. From these measurements, a failure analysis methodology flow chart (Fig. 7) is pro- posed to performa comprehensive AFManalysis on cross- sections of integrated devices. The flow chart starts with the cross-sectioning of the sample. As a function of the materials, localization, and technology, several techniques can be used: automated cleaving, mechanical polishing, ionic polishing, or focused ion beam (FIB) preparation. For SCM, the presence of a thin oxide at the sample surface is necessary, which can be native, thermally, or UV induced. SCMmode canbe replacedby scanningnonlinear dielectric microscopy (SNDM). When the cross section is prepared, a localizationof the interesting area is necessary with a simple topographymode todetermine the scan size and verify the quality (low roughness) of the surface. After that, when the back contact is made with the AFM chuck, SCM and SSRM investigations in the multidimensional approach (as a function of the applied V DC ) allow one to determine the optimum V DC to be applied to reveal the real structure of the studied sample, compare samples and conclude on the failure analysis. ACKNOWLEDGMENTS The authors thank the Réseaux d’Intérêts Normands RIN PLACENANO for their financial support, and NXP Semiconductors Caen for the sample. We thank Denis Mariolle and Nicolas Chevalier from CEA Leti for fruitful discussions. REFERENCES 1. W. Vandervorst, et al.: “Dopant, Composition and Carrier Profiling for 3D Structures,” Materials Science in Semiconductor Processing, Vol. 62, 2017, p. 31–48 , DOI: 10.1016/j.mssp.2016.10.029. 2. R.A. Oliver: “Advances in AFM for the Electrical Characterization of Semiconductors,” Rep. Prog. Phys., Vol. 71, No. 7, 2008, p. 076501, DOI: 10.1088/0034-4885/71/7/076501 . 3. R.C. Germanicus, et al.: “Mapping of Integrated PIN Diodes with a 3D Architecture by ScanningMicrowave ImpedanceMicroscopy and Dynamic Spectroscopy,” Beilstein J. Nanotechnol., Vol. 11, No. 1, 2020, p. 1764–1775, DOI: 10.3762/bjnano.11.159. 4. R.C. Germanicus, et al.: “On the Effects of a Pressure Induced Amorphous Silicon Layer on Consecutive Spreading Resistance Microscopy Scans of Doped Silicon,” J. Appl. Phys., Vol. 117, No. 24, 2015, p. 244306 , DOI: 10.1063/1.4923052. 5. R.C. Germanicus, et al.: “Dopant Activity for Highly in-situ Doped Polycrystalline Silicon: Hall, XRD, Scanning CapacitanceMicroscopy (SCM) andScanning Spreading ResistanceMicroscopy (SSRM),” Nano Ex., Vol. 2, No. 1, 2021, p. 010037, DOI: 10.1088/2632-959X/abed3e . ABOUT THE AUTHORS Rosine Coq Germanicus is an assistant teaching professor at CRISMAT (Laboratoire de Cristallographie et Sciences des Matériaux) at the University of Caen in Normandy, France. After a university degree in physics at Guadeloupe, she received her Ph.D. at the University Montpellier 2, France, in space radiation effects on optoelectronic devices. Her current research activity focuses on scanning probe microscopy for microelectronic devices and radiation effects. Her research includes nano-electrical, nano-mechanical characterizations, failure analysis, and reli- ability of integrated semiconductor devices. Ulrike Lüders is research director at the CNRS, carrying out her research activities at the CRISMAT (Laboratoire de Cristallographie et Sciences des Matériaux) in Caen, France. Her research interests are mainly focused on the growth and characterization of oxide thin films, superlattices, and laminates, having exotic transport, dielectric, or magnetic properties for application in future generation inte- grated electronics. In the recent years, her research activities evolved to the in-depth characterization of semiconductor-based systems.