High-Resolution 3D Imaging Microscopy Using Hard X-Rays

Abstract

The key strength of hard x-ray full-field microscopy is the large penetration depth of hard x-rays into matter, which allows one to image the interior of opaque objects. Combined with tomographic techniques, the three-dimensional inner structure of an object can be reconstructed without the need for difficult and destructive sample preparation. Projection microscopy and microtomography are now routinely available at synchrotron radiation sources. The resolution of these techniques is limited by that of the detector to 1 µm or slightly less. X-ray images and tomograms at higher spatial resolution can be obtained by x-ray optical magnification, for example, by using parabolic refractive x-ray lenses as a magnifying optic. Combining magnifying x-ray imaging with tomography allows one to reconstruct the three-dimensional structure of an object, such as a microprocessor chip, with resolution well below 1 µm. In x-ray scanning microscopy, the sample is scanned through a small-diameter beam. The great advantage of scanning microscopy is that x-ray analytical techniques such as fluorescence analysis, diffraction, and absorption spectroscopy can be used as contrast mechanisms in the microscope. In combination with tomography, fluorescence analysis makes it possible to reconstruct the distribution of different chemical elements inside an object (fluorescence microtomography), while combining absorption spectroscopy with tomography yields the distribution of different oxidation states of atomic species.

A General Methodology for Full-Field Plastic Strain Measurements Using X-ray Absorption Tomography and Internal Markers

“…From these absorption images, the local X-ray attenuation coefficient can then be reconstructed for each point in the sample with a resolution dependent on the experiment and detector pixel size. Applications of X-ray micro-tomography in Materials Science have been reviewed by Salvo et al [17] and Schroer et al [18].…”

Volume‐Resolved Nanostructure Survey of a Polymer Part by Means of SAXS Microtomography

“…On the other hand, the lateral spatial resolution can be diminished by means of microbeam optics. [3][4][5] At the synchrotron beamlines of HASYLAB, Hamburg a microbeam was not available for scattering studies of soft matter until recently; X-ray focusing beryllium lenses [6][7][8][9][10][11][12][13][14][15][16][17] have now been introduced. As the diameter of the primary beam is demagnified to several micrometers, the mechanical slicing of the material can advantageously be replaced by a mathematical treatment of recordable projected scattering data based on the Fourier slice-theorem.…”

Efficient focusing of 8 keV X-rays with multilayer Fresnel zone plates fabricated by atomic layer deposition and focused ion beam milling

“…In contrast to electron microscopy, X-ray microscopy provides high penetration depth and enables three-dimensional imaging of complete cells (Vogt et al, 2000), large alive biological samples (Olendrowitz et al, 2012) and in situ investigation under extreme conditions (Fife et al, 2012). As the theoretical resolution is determined by the wavelength, hard X-ray microscopy is a very promising technique for highresolution imaging with chemical sensitivity (Schroer et al, 2004). Unfortunately, the focusing optics for hard X-rays are limited in terms of resolution and/or diffraction efficiency (DE).…”