An in-vacuum x-ray diffraction microscope for use in the 0.7-2.9 keV range

• Published in: Review of scientific instruments 2012-03, Vol.83 (3), p.033703-033703-5
• Main Authors: Vine, D. J., Williams, G. J., Clark, J. N., Putkunz, C. T., Pfeifer, M. A., Legnini, D., Roehrig, C., Wrobel, E., Huwald, E., van Riessen, G., Abbey, B., Beetz, T., Irwin, J., Feser, M., Hornberger, B., McNulty, I., Nugent, K. A., Peele, A. G.
• Format: Article
• Language: English
• ISSN: 0034-6748; 1089-7623
• DOI: 10.1063/1.3688655

A dedicated in-vacuum coherent x-ray diffraction microscope was installed at the 2-ID-B beamline of the Advanced Photon Source for use with 0.7-2.9 keV x-rays. The instrument can accommodate three common implementations of diffractive imaging; plane wave illumination; defocused-probe (Fresnel diffractive imaging) and scanning (ptychography) using either a pinhole, focused or defocused probe. The microscope design includes active feedback to limit motion of the optics with respect to the sample. Upper bounds on the relative optics-to-sample displacement have been measured to be 5.8 nm(v) and 4.4 nm(h) rms/h using capacitance micrometry and 27 nm/h using x-ray point projection imaging. The stability of the measurement platform and in-vacuum operation allows for long exposure times, high signal-to-noise and large dynamic range two-dimensional intensity measurements to be acquired. Finally, we illustrate the microscope's stability with a recent experimental result.