Beryllium window and acoustic delay line design for x-ray lithography beam lines at the university of Wisconsin center for x-ray lithography

X‐ray lithography systems require sample chambers that can perform exposures in helium gas at atmospheric pressure. The interface between the experimental chamber and the beamline is critical for x‐ray lithography and the storage ring. It must allow a high x‐ray flux throughput while providing a vacuum barrier so that helium gas does not leak into the beam line and the storage ring. The beam line must also be designed to have protection in the case that a window does fail in order to minimize adverse effects to the ring and other systems. The details of the design for the vacuum system used on beam lines for the Center for X‐ray Lithography at the University of Wisconsin Synchrotron Radiation Center 1‐GeV electron storage ring are reported. Curved beryllium windows with a 1×5‐cm2 aperture and 13 μm thick that have a leak rate less than 10−10 Torr l/s have been successfully used at the experimental chamber beam‐line interface. This thin flat beryllium foil is mounted in a curved housing with a wire seal to...