Fabrication of X-ray absorption gratings by centrifugal deposition of bimodal tungsten particles in high aspect ratio silicon templates.
Fabrication of X-ray absorption gratings by centrifugal deposition of bimodal tungsten particles in high aspect ratio silicon templates.
复制标题
通过在高纵横比硅模板中离心沉积双峰钨粒子，制造 X 射线吸收光栅。
DOI：
10.1038/s41598-022-08222-z
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发表时间：
2022-03-30
影响因子：
4.6
通讯作者：
Pfeiffer F
中科院分区：
文献类型：
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作者：
Pinzek S;Gustschin A;Gustschin N;Viermetz M;Pfeiffer F
基于光栅的x射线成像采用高宽高比吸收光栅来产生由被成像物体的衰减、相移和小角度散射特性引起的对比度。吸收光栅的制作仍然是该方法走向临床应用的关键挑战。我们探索了一种简单、快速的离心钨颗粒沉积成硅蚀刻光栅模板的工艺，它比传统的方法具有决定性的优势。为此，我们使用双峰钨颗粒悬浮液，将其引入定制设计的光栅支架并在1000×g上离心。周期为45µm，深度为450µm，有效面积为170 mm × 38 mm的光栅成功加工，达到均匀的吸收器填充。有效吸收钨厚度为207µm，填充率为46.6%。该光栅在专为临床x射线暗场计算机断层扫描设计的塔尔博特-劳干涉仪中进行了测试，在60 kV下的可见度高达33.6%。
Grating-based X-ray imaging employs high aspect ratio absorption gratings to generate contrast induced by attenuating, phase-shifting, and small-angle scattering properties of the imaged object. The fabrication of the absorption gratings remains a crucial challenge of the method on its pathway to clinical applications. We explore a simple and fast centrifugal tungsten particle deposition process into silicon-etched grating templates, which has decisive advantages over conventional methods. For that, we use a bimodal tungsten particle suspension which is introduced into a custom designed grating holder and centrifuged at over 1000×g. Gratings with 45 µm period, 450 µm depth, and 170 mm × 38 mm active area are successfully processed reaching a homogeneous absorber filling. The effective absorbing tungsten thickness in the trenches is 207 µm resulting in a filling ratio of 46.6% compared to a voidless filling. The grating was tested in a Talbot–Lau interferometer designed for clinical X-ray dark-field computed tomography, where visibilities up to 33.6% at 60 kV were achieved.