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The current capabilities of and future upgrade plans for the beamlines supporting structural biology at the Canadian Light Source are described., The Canadian Macromolecular Crystallography Facility (CMCF) consists of two beamlines dedicated to macromolecular crystallography: CMCF-ID and CMCF-BM. After the first experiments were conducted in 2006, the facility has seen a sharp increase in usage and has produced a significant amount of data for the Canadian crystallographic community. Upgrades aimed at increasing throughput and flux to support the next generation of more demanding experiments are currently under way or have recently been completed. At CMCF-BM, this includes an enhanced monochromator, automounter software upgrades and a much faster detector. CMCF-ID will receive a major upgrade including a new undulator, a new monochromator and new optics to stably focus the beam onto a smaller sample size, as well as a brand-new detector.

Spectrographs take snapshots of photon spectra with array detectors by dispersing photons of different energies into distinct directions and spacial locations. Spectrographs require optics with a large angular dispersion rate as the key component. In visible light optics diffraction gratings are used for this purpose. In the hard x-ray regime, achieving large dispersion rates is a challenge. Here we show that multi-crystal, multi-Bragg-reflection arrangements feature cumulative angular dispersion rates almost two orders of magnitude larger than those attainable with a single Bragg reflection. As a result, the multi-crystal arrangements become potential dispersing elements of hard x-ray spectrographs. The hard x-ray spectrograph principles are demonstrated by imaging a spectrum of photons with a record high resolution of $\Delta E \simeq 90 \mu$eV in hard x-ray regime, using multi-crystal optics as dispersing element. The spectrographs can boost research using inelastic ultra-high-resolution x-ray spectroscopies with synchrotrons and seeded XFELs.

We report on the design, implementation, and performance of an x-ray monochromator with ultra-high energy resolution (ΔE/E ≃ 2.7 × 10(-8)) and high spectral efficiency using x rays with photon energies E ≃ 9.13 keV. The operating principle of the monochromator is based on the phenomenon of angular dispersion in Bragg back-diffraction. The optical scheme of the monochromator is a modification of a scheme reported earlier [Shvyd'ko et al., Phys. Rev. A 84, 053823 (2011)], where a collimator/wavelength selector Si crystal was replaced with a 100-μm-thick type IIa diamond crystal. This modification provides a very-small-energy bandwidth ΔE ≃ 0.25 meV, a 3-fold increase in the aperture of the accepted beam, a reduction in the cumulative angular dispersion rate of x rays emanating from the monochromator for better focusing on a sample, a sufficient angular acceptance matching the angular divergence of an undulator source (≈ 10 μrad), and an improved throughput due to low x-ray absorption in the thin diamond crystal. The measured spectral efficiency of the monochromator was ≈ 65% with an aperture of 0.3 × 1 mm(2). The performance parameters of the monochromator are suitable for inelastic x-ray spectroscopy with an absolute energy resolution ΔE1 meV.

In this study, the thermomechanical characteristics of copper through-silicon via (Cu TSV) structures were studied using synchrotron x-ray microdiffraction, electron backscattered diffraction (EBSD), and nonlinear numerical modeling. The strain and stress distribution in the Si substrate was measured by synchrotron x-ray microdiffraction from the tops of the TSV structures. The strain distribution map in a Cu via was determined from EBSD data by the kernel average misorientation (KAM) method and microstructural characteristics of the Cu via were investigated. The results offered direct evaluation of the local strain and stress induced in the Cu via and its surrounding silicon substrate. A finite element model including nonlinear plastic deformation was built for predicting thermomechanical behaviors of Cu TSV structures. The results show that the stress distribution obtained by finite element modeling is in relatively good agreement with the measurements of synchrotron x-ray microdiffraction and EBSD.