Hard X-ray full-field nanoimaging using a direct photon-counting detector

J Synchrotron Radiat. 2023 Mar 1;30(Pt 2):390-399. doi: 10.1107/S1600577522012103. Epub 2023 Feb 1.

Abstract

Full-field X-ray nanoimaging is a widely used tool in a broad range of scientific areas. In particular, for low-absorbing biological or medical samples, phase contrast methods have to be considered. Three well established phase contrast methods at the nanoscale are transmission X-ray microscopy with Zernike phase contrast, near-field holography and near-field ptychography. The high spatial resolution, however, often comes with the drawback of a lower signal-to-noise ratio and significantly longer scan times, compared with microimaging. In order to tackle these challenges a single-photon-counting detector has been implemented at the nanoimaging endstation of the beamline P05 at PETRA III (DESY, Hamburg) operated by Helmholtz-Zentrum Hereon. Thanks to the long sample-to-detector distance available, spatial resolutions of below 100 nm were reached in all three presented nanoimaging techniques. This work shows that a single-photon-counting detector in combination with a long sample-to-detector distance allows one to increase the time resolution for in situ nanoimaging, while keeping a high signal-to-noise level.

Keywords: Zernike phase contrast; full-field X-ray microscopy; nanotomography; near-field holography; near-field ptychography; phase contrast; single-photon-counting detector.