Fabrication of uniformly redundant arrays and Young's slits for coherence measurements in x-rays

摘要

We have perfected a micromachining technology based on microlithography and electroforming for producing uniformly redundant arrays (URA) and Young's slits for coherence measurements in synchrotron radiation beamlines. The structures may act as absorbent objects or as phase objects. Two microfabrication techniques were used. Optical lithography in thin photoresists followed by gold electroforming on silicon nitride membranes produced structures 0.5-2.0 μm thick. Soft x-ray lithography in thick resists using the structures produced by optical lithography as a mask, followed by gold electroforming, produced structures up to 6.3 μm thick. Young s slits, one dimensional (1D), and two dimensional (2D) URA structures with feature sizes as small as 1 μm were produced in this way and used for coherence measurements in the soft and hard x-ray regimes at the Advanced Photon Source.