X-ray phase imaging using a Gd-based absorption grating fabricated by imprinting technique

Abstract

A high-aspect-ratio absorption grating with a pitch of several µm is a key component of X-ray grating interferometery, which is an X-ray phase imaging technique that allows for highly sensitive X-ray imaging with a compact laboratory X-ray source. Here, we report that X-ray phase imaging was successfully performed at 15 keV by using a 23 ± 1-µm-height, 9-µm-pitch absorption grating (10 × 10 mm2) based on Gd (Gd60Cu25Al15) fabricated by a metallic glass imprinting technique. The imprinting technique is cost-efficient and has a high-production rate, and will be widely used for fabricating gratings not only for X-rays but also neutrons in the near future.

Gadolinium oblique evaporation approach to make large scale neutron absorption gratings for phase imaging

“…Some grating fabrication methods have been proposed. [16][17][18] In our previous study, we fabricated a 20 mm square Gd neutron absorption grating whose height, pitch and duty cycle were 12 μm, 9 μm and 0.5 respectively. A Talbot-Lau interferometer was successfully constructed for neutron phase imaging at the neutron radiography station RADEN (BL22), J-PARC, Japan.…”

Fabrication of X-ray absorption grating using an ultracentrifuge machine

“…Although it is difficult to fabricate high-aspect-ratio hard-X-ray optics, several approaches have so far been reported for X-ray absorption grating. [37][38][39][40][41][42][43][44][45][46][47][48][49][50][51][52][53][54][55][56] Electroplating techniques combined with X-ray lithography [38][39][40][41]43,45,50,54) and deep etching 37,42,57) have so far been widely used. They have provided high-quality and large-area X-ray absorption gratings, and the technique combined with deep dry etching 42,57) should be promising in terms of cost-effectiveness, but electroplating normally requires more than a few hours for a few tens of μm thickness.…”

“…They have provided high-quality and large-area X-ray absorption gratings, and the technique combined with deep dry etching 42,57) should be promising in terms of cost-effectiveness, but electroplating normally requires more than a few hours for a few tens of μm thickness. Recently, high-throughput techniques such as microcasting 46,47,51,55,56) and metallic glass imprinting 48,52,53) were proposed. Although they are low-cost and the imprinting technique can also be used even for neutron absorption grating, 58,59) specific materials, in which atomic density of heavy atoms are not necessarily high, are required.…”

An 8-inch absorption grating used in cascaded Talbot-Lau interferometers for X-ray phase-contrast imaging

“…Imprinting technology was used to fabricate low-cost absorption gratings based on metallic glass, such as Pd 42.5 Ni 7.5 Cu 30 P 20 and Gd 60 Cu 25 Al 15 . 20,21) However, the absorptivity of these materials is lower than that of heavy elements. Recently, absorption gratings fabricated with tungsten and gold particles were reported, and they showed good performances in X-ray absorption.…”