Enhancing full-field TXM with low emittance synchrotron sources: Mono-capillary condenser shaker optimization

Synchrotron radiation based full-field transmission hard x-ray microscope (TXM) achieves spatial resolutions ranging from a few to tens of nanometers. The field of view (FOV) and resolution are contingent upon the illumination characteristics of the condenser, the zone plate, and the detector. With the technological advancements in synchrotron radiation accelerators, there has been a progressive reduction in the electron beam emittance. The focused spot by the condenser in TXM systems utilizing a mono-capillary condenser has also become smaller, consequently narrowing the TXM's FOV. Additionally, due to slope errors of the mono-capillary condenser, the focused spot is non-uniform, leading to a non-uniform FOV in TXM. To address these issues, a condenser shaker has been implemented. This study presents theoretical analysis, simulations, and experimental data, illustrating the impacts of different amplitudes and frequencies of the condenser shaker on the focused spot, TXM's FOV, and imaging quality. The results indicate that the FOV of TXM increases nearly double when the condenser shaker is optimally applied, compared to its absence. These enhancements signify that the optimization of mono-capillary condenser shaking in the TXM system can expand the FOV and significantly enhance the overall imaging quality. Through this optimization, three-dimensional nano-imaging of a battery particle with a 28 μm diameter and 96 nm micro-structures was successfully achieved.