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Diffraction-based techniques, with either electrons or photons, are commonly used in materials science to measure elastic strain in crystalline specimens. In this paper, the focus is on two advanced techniques capable of accessing strain information at the nanoscale: high-resolution X-ray diffraction (HRXRD) and the transmission electron microscopy technique of dark-field electron holography (DFEH). Both experimentally record an image formed by a diffracted beam: a map of the intensity in the vicinity of a Bragg reflection spot in the former, and an interference pattern in the latter. The theory that governs these experiments will be described in a unified framework. The role of the geometric phase, which encodes the displacement field of a set of atomic planes in the resulting diffracted beam, is emphasized. A detailed comparison of experimental results acquired at a synchrotron and with a state-of-the-art transmission electron microscope is presented for the same test structure: an array of dummy metal–oxide–semiconductor field-effect transistors (MOSFETs) from the 22 nm technology node. Both techniques give access to accurate strain information. Experiment, theory and modelling allow the illustration of the similarities and inherent differences between the HRXRD and DFEH techniques.

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In advanced transistor technology, Silicon‐Germanium alloy (SiGe) is being used as a replacement for Si channels to achieve higher mobility. Among the various characterization techniques μ‐Raman spectroscopy is a promising candidate due to a good spatial resolution and low detection threshold. This study presents the evaluation of the technique for the measurement of Ge concentration and comparison to other metrology techniques. As a first step to evaluate the μ‐Raman capability, we considered a simple case of thin SiGe films from 12nm down to 4 nm thickness. Assuming an epitaxial pseudomorphic structure, the Ge content has been extracted for all samples with an average 0.3% stability and at least 1% accuracy as confirmed by high resolution X‐ray diffraction (HRXRD) and secondary ion mass spectrometry analysis (SIMS). We then studied a more complex structure of SiGe on fully depleted‐silicon on insulator (FD‐SOI) as being critical for the development of condensation process of advanced transistor technology. Since μ‐Raman requires prior knowledge of the structural state of the layer, we discuss the interest to combine μ‐Raman measurements with X‐rays diffraction in order to extract the Ge composition on such stacks. μ‐Raman shows a real potential for thin SiGe film characterization and it does not suffers of the lack of precision for very thin films as HRXRD does, however there are still some developments to be made before using it as a metrology technique. Moreover, it could be interesting to couple the technique with HRXRD measurement. The approach to control SiGe condensation process on FD‐SOI might suggest interesting experiment. (© 2015 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)