Silicon saw-tooth refractive lens for high-energy X-rays made using a diamond saw

Abstract

Silicon is a material well suited for refractive lenses operating at high X-ray energies (> 50 keV), particularly if implemented in a single-crystal form to minimize small-angle scattering. A single-crystal silicon saw-tooth refractive lens, fabricated by a dicing process using a thin diamond wheel, was tested with 115 keV X-rays, giving an ideal 17 mm line focus width in a long focal length, 2 : 1 ratio demagnification geometry, with a source-to-focus distance of 58.5 m. The fabrication is simple, using resources typically available at any synchrotron facility's optics shop.

Far-Field High-Energy Diffraction Microscopy: A Non-Destructive Tool for Characterizing the Microstructure and Micromechanical State of Polycrystalline Materials

“…Furthermore, when combined with high-energy X-ray tomography, a wide range of features at various length scales in a material can be characterized. With recent advances in focusing optics suitable for high-energy X-rays, ~1-10 µm spot size is routinely achievable at a wide range of energies [13][14], and sub-µm spot size also has been achieved [15]. The spot size is anticipated to improve significantly as emittance of the electron beam in the storage ring is reduced with the introduction of fourth-generation synchrotron sources.…”

“…Analogous to non-destructive 3D electron backscatter diffraction view of a polycrystalline aggregate using a line focused beam [13][14]. Does not provide strain information.…”

Quantifying Three-Dimensional Residual Stress Distributions Using Spatially-Resolved Diffraction Measurements and Finite Element Based Data Reduction

“…The monochromatic x-ray beam used in this work was focused using the x-ray optics described in [41] and the final beam size was 50 µm along the y L direction and 50 µm along the x L . The wavelength of the beam used to measure the lattice strains in the interference fit sample was 0.02000 nm (61.99 keV).…”

High transmission Ni compound refractive lens for high energy X-rays

“…1 Since then, various types of lenses have been invented, described and tested. 2 The most popular is parabolic compound refractive lens (CRL) which is also the subject of present paper; however the so-called sawtooth 3,4 and kinoform 5 lenses are frequently used. Although CRL poses a drawback of the small effective aperture, it has several advantages.…”

“…Successful application of tunable silicon saw-tooth lenses for high energy X-rays was presented by the group from APS. The lenses were produced by the dicing technique with the use of a diamond wheel and they were able to produce a 17 µm line focus for 115 keV X-rays, 4 but for getting the smaller focus size more sophisticated microfabrication methods like reactive ion etching or electroforming are needed. 3 Also to get the aberration free focused beam, a high precision positioning a) Author to whom correspondence should be addressed.…”