The open-source PyNX toolkit has been extended to provide tools for coherent X-ray imaging data analysis and simulation. All calculations can be executed on graphical processing units (GPUs) to achieve high-performance computing speeds. The toolkit can be used for coherent diffraction imaging (CDI), ptychography and wavefront propagation, in the far- or near-field regime. Moreover, all imaging operations (propagation, projections, algorithm cycles…) can be implemented in Python as simple mathematical operators, an approach which can be used to easily combine basic algorithms in a tailored chain. Calculations can also be distributed to multiple GPUs, e.g. for large ptychography data sets. Command-line scripts are available for on-line CDI and ptychography analysis, either from raw beamline data sets or using the coherent X-ray imaging data format.

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Strain engineered performance enhancement in SiGe channels for p-MOSFETs is one of the main drivers for the development of microelectronic technologies. Thus, there is a need for precise and accurate strain mapping techniques with small beams. Scanning X-Ray Diffraction Microscopy (SXDM) is a versatile tool that allows measuring quantitative strain maps on islands as thin as 13 nm quickly. From the high velocity and robustness of the technique, statistical information can be extracted for a large number of individual islands of different sizes. In this paper, we used the advantages of SXDM to demonstrate the effectiveness of the condensation method used to grow ultra-thin layers of strained SiGe and to determine their relaxation lengths at patterned interfaces.

Coherent X-ray Diffraction Imaging (CXDI) has seen remarkable developments during the last 15 years, allowing not only to recover the 2D and 3D electronic density of single nano-objects with a resolution up to about 10 nm, but also (using the Bragg geometry) the inhomogeneous strain of deformed crystal lattices. This quantitative analysis can be performed either using standard CXDI [1], or using Ptychography, either in 3D or using the back-projection approach [2].We will present studies of semiconductor nanostructures, firstly with 70 and 20 nm thick lines and islands made of strained silicon or silicon-germanium on insulator. In these samples the strain is used to enhance the conductive properties for electronic (transistor) applications. Secondly, we will present results on GaAs nanowire with embedded InAs quantum dots used as source for single photon emission.Finally, we will discuss the future of X-ray coherent imaging techniques, which will become more accessible with the development of more user-friendly algorithms and software for data analysis [3], and the prospect of more brilliant sources giving several orders of magnitude improvement in the available coherent flux.Figure caption: Reconstruction of a GaAs nanowire with an ~1.7 monolayer InAs insertion in Bragg geometry. The brightness corresponds to the amplitude, the colour to the phase of the complex image -corresponding to a ~0.027nm shift of the crystalline lattice. Inset: reconstructed X-ray probe.