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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.

UV lithography has been used in most case of microstructure patterning. However, it is difficult to form a fine rectangular microstructure in the thin film at a small width. On the other hand, silicon dry etching technology makes it possible to fabricate rectangular structures by repeating two steps of etching process and protection process. Then, we introduce the ability of Si dry etching technology in order to fabricate un-tapered, high precision Au microstructures containing rectangular patterns in order to fabricate Au microstructures. Au electroforming was realized from the bottom of the Si microstructure groove. We succeeded in forming about 4 m thick, void-free Au film in a space as narrow as 2.6 m in large effective area of 60 mm squares on 4 inch Si wafer. Therefore, it is expected to be used in the production of a wide variety of devices that have not yet been put into practice.

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X-ray radiographic imaging techniques have been applied in many fields. Previously we proposed a method for X-ray phase imaging using X-ray Talbot interferometry which requires the use of X-ray gratings. In this work, we fabricated the X-ray gratings needed for X-ray Talbot interferometry using an X-ray lithography technique. For X-ray lithography the accuracy of the fabricated structure depends largely on the accuracy of the X-ray mask. Conventionally a resin material is used for the support membrane for large area X-ray masks. However, resin membranes have the disadvantage that they can sag after several cycles of X-ray exposure due to the heat generated by the X-rays. For our new proposal we used thin carbon wafers for the membrane material because carbon has an extremely small thermal expansion coefficient. This new type of X-ray mask is very easy to process, and it is expected that it will lead to more precise X-ray masks. We fabricated carbon membrane X-ray masks on 6 inch wafers with a 1:1 line-to-space ratio and a pitch of 5.3 μm, covering a large effective area of 100 × 100 mm2.