European Synchrotron Radiation Facility, 38000 Grenoble, France.
J Synchrotron Radiat. 2019 Sep 1;26(Pt 5):1751-1762. doi: 10.1107/S1600577519006301. Epub 2019 Jul 12.
X-ray ptychography is a coherent diffraction imaging technique with a high resolving power and excellent quantitative capabilities. Although very popular in synchrotron facilities nowadays, its implementation with X-ray energies above 15 keV is very rare due to the challenges imposed by the high energies. Here, the implementation of high-energy X-ray ptychography at 17 and 33.6 keV is demonstrated and solutions to overcome the important challenges are provided. Among the particular aspects addressed are the use of an efficient high-energy detector, a long synchrotron beamline for the high degree of spatial coherence, a beam with 1% monochromaticity providing high flux, and efficient multilayer coated Kirkpatrick-Baez X-ray optics to shape the beam. The constraints imposed by the large energy bandwidth are carefully analyzed, as well as the requirements to sample correctly the high-energy diffraction patterns with small speckle size. In this context, optimized scanning trajectories allow the total acquisition time to be reduced by up to 35%. The paper explores these innovative solutions at the ID16A nano-imaging beamline by ptychographic imaging of a 200 nm-thick gold lithography sample.
X 射线相衬层析成像技术是一种具有高分辨率和出色定量能力的相干衍射成像技术。尽管它在当今的同步加速器设施中非常流行，但由于高能带来的挑战，其在 15keV 以上的 X 射线能量下的应用非常罕见。本文展示了在 17keV 和 33.6keV 下实现高能 X 射线相衬层析成像的方法，并提供了克服重要挑战的解决方案。其中解决的特殊问题包括使用高效的高能探测器、具有高空间相干度的长同步加速器光束线、具有 1%单色性的光束以提供高通量，以及高效的多层镀膜 Kirkpatrick-Baez X 射线光学元件来对光束进行整形。本文还仔细分析了大能量带宽带来的限制，以及正确采集小散斑尺寸的高能衍射图案的要求。在这种情况下，优化的扫描轨迹可以将总采集时间减少多达 35%。本文还通过对 200nm 厚的金光刻样品进行相衬成像，在 ID16A 纳米成像光束线上探索了这些创新的解决方案。
