Accurate depth profiling of dry oxidized SiGeC thin films by extended Full Spectrum ToF-SIMS

• Published in: Applied surface science Vol. 257; no. 22; pp. 9414 - 9419
• Main Authors: Py, M., Saracco, E., Damlencourt, J.F., Barnes, J.P., Fabbri, J.M., Hartmann, J.M.
• Format: Journal Article
• Language: English
• Published: Amsterdam Elsevier B.V 01.09.2011; Elsevier
• Subjects: Annealing; Atomic, molecular, and ion beam impact and interactions with surfaces; Chemical composition analysis, chemical depth and dopant profiling; Condensed matter: electronic structure, electrical, magnetic, and optical properties; Cross-disciplinary physics: materials science; rheology; Depth profiling; Devices; Electron and ion emission by liquids and solids; impact phenomena; Exact sciences and technology; Full Spectrum; Ge condensation; Germanium; Impact phenomena (including electron spectra and sputtering); Impurities; Materials science; Materials testing; Nanostructure; Physics; Secondary ion mass spectrometry; Silicon germanides; Silicon Germanium; Thin films; ToF-SIMS; ToF-SIMS; Full Spectrum; Silicon Germanium; Ge condensation; Annealing; Inorganic compounds; Ge-Si alloys; Three-dimensional systems; Vapor condensation; Germanium compounds; Oxidizing atmosphere; Silicon compounds; Thin films; SIMS; Nanowires; Carbon compounds; Matrix elements; Nanostructured materials; Depth profiles
• ISSN: 0169-4332; 1873-5584
• DOI: 10.1016/j.apsusc.2011.06.021

► Oxidation of SiGeC blanket layers for Ge enrichment is studied with ToF-SIMS. ► An original quantification protocol, the extended Full Spectrum protocol, is used. ► Improvements brought by this protocol over more classic ones are highlighted. ► This study yields useful information for comprehension of the oxidation mechanisms. The abundance of work on SiGe based devices demonstrates the importance of compositional characterization of such materials. However accurate SIMS depth profiling of SiGe, and especially of SiGe/silicon dioxide interfaces can be difficult due to matrix effects. Therefore, we highlight here the improvements brought by the extended Full Spectrum protocol, presented in previous works and allowing minimization of matrix effects. Previous studies on this protocol showed that it was extremely precise and reproducible for Ge and impurity quantification in non oxidized matrices. In this study we thus investigated its accuracy for simultaneous quantitative depth profiling of both matrix elements (Si, Ge, O) and impurities (C) in Si 0.82Ge 0.16C 0.02 layers annealed in oxidizing atmosphere, by comparing results with more classic protocols. The profiles provided by the extended Full Spectrum protocol were found to be more accurate than the others, especially around interfaces. This results in a better comprehension of the behaviour of SiGeC layers under oxidizing anneal and thus allows the fabrication of very well controlled three dimensional Ge nanowire structures for next generation devices.