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arXiv · 2102.12359

Fabrication of astronomical x-ray reflection gratings using thermally activated selective topography equilibration

Jake A. McCoy·Randall L. McEntaffer·Chad M. Eichfeld
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Abstract

Thermally activated selective topography equilibration (TASTE) enables the creation of 3D structures in resist using grayscale electron-beam lithography followed by a thermal treatment to induce a selective polymer reflow. A blazed grating topography can be created by reflowing repeating staircase patterns in resist into wedge-like structures. Motivated by astronomical applications, such patterns with periodicities 840 nm and 400 nm have been fabricated in 130 nm-thick PMMA using TASTE to provide a base for X-ray reflection gratings. A path forward to integrate this alternative blazing technique into grating fabrication recipes is discussed.

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Jake A. McCoy, Randall L. McEntaffer, Chad M. Eichfeld. 2021-02-02. Fabrication of astronomical x-ray reflection gratings using thermally activated selective topography equilibration. https://doi.org/10.1116/1.5048197

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