Fabrication of Si Mold Using ICP Etching for X-Ray Diffraction Grating

Abstract

We have fabricated X-ray diffraction gratings for X-ray phase imaging using X-ray Talbot interferometer. In this paper, we propose the new low cost fabrication process using Si mold of Si dry etching and nano-imprint techniques. Si dry etching makes it possible to fabricate high aspect ratio rectangular microstructures. Therefore, this technique is expected to fabricate high precision grating pattern. In this paper, we propose the new low cost fabrication processes using Si mold of ICP-RIE and nano-imprint techniques. And, in order to form transparence imprint mold, we used thermal oxidation of Si mold. These demonstrations of thermal oxidation are promising method for high precision transparence imprint mold with low cost, and realized low cost optical device such as diffraction gratings.

Nanofabrication and characterization of high-line-density x-ray transmission gratings

“…Currently, the methods for manufacturing high-linedensity gratings include interference lithography plus deep reactive ion etching, 12,13 interference lithography followed by anisotropic Si wet etching, 14,15 nanoimprint and multistep etching, 16 ion beam lithography, 17,18 etc. In addition, electron beam lithography (EBL) and its combination with other nanofabrication technologies are of great interest for fabricating x-ray diffractive optical elements including x-ray TGs.…”

“…In addition, electron beam lithography (EBL) and its combination with other nanofabrication technologies are of great interest for fabricating x-ray diffractive optical elements including x-ray TGs. [9][10][11][12][13][14][15][16][17][18][19][20][21] EBL tools have been developed with a fast 100-MHz line frequency and a beam diameter of several nanometers. 22 A remarkable progress has also been made in which nanostructures with a high aspect ratio of up to 20 nm and patterns with 4.5-nm half-pitch have been achieved by a single EBL step.…”

“…26 However, every above-mentioned lithographic method has strengths and weaknesses and still suffers from many challenges such as sophisticated deepreactive-ion etching process, mask fabrication, and low writing speed. 12,16,19 Here, we report on our recent progress on nanofabrication and characterization of high-line-density x-ray TGs. On one hand, to fabricate 6666 lines∕mm x-ray TGs, EBL was used to directly write patterns on the membrane of low-z material and combined with ultraviolet lithography (UVL) to define supporting frames.…”