Matrix effects in Si1−xGex structures under O2+ and Cs+ bombardment were studied. Matrix effects were practically suppressed with Cs2Ge+ secondary ions, for Ge concentrations of between 0 and 100at%. A procedure for the accurate quantification of the Ge concentration in Si1−xGex alloys, using Cs2Ge+ and CsGe+ clusters, was proposed. For structures in which the Ge content was constant over several hundreds of nm, both methods provided very similar results, with excellent agreement between the Ge concentrations measured by secondary ions mass spectrometry and X-ray diffraction. However, for continuously varying Ge concentration profiles, the non-linear response of the CsGe+ normalized intensity and the persistence of strong matrix effects for CsSi+ ions led to differences between the Ge concentration profiles measured with the CsGe+ method as compared to the Cs2Ge+ one. The latter was therefore the only reliable method for the study of Ge in-diffusion into Si from a pure Ge layer grown by chemical vapor deposition. An application of this method to the analysis of Ge in-diffusion in Si at 900C was also reported.

Detection of Cs2Ge+ Clusters for the Quantification of Germanium Atoms by Secondary Ion Mass Spectrometry - Application to the Characterization of Si1-xGex Layers (0 ≤ x ≤ 1) and Germanium Diffusion in Silicon. M.Gavelle, E.Scheid, F.Cristiano, C.Armand, J.M.Hartmann, Y.Campidelli, A.Halimaoui, P.F.Fazzini, O.Marcelot: Journal of Applied Physics, 2007, 102[7], 074904