Fabrication and preliminary testing of regular microporous membranes manufactured by deep X-ray lithography at the VEPP-3 storage ring

Regular microporous membranes with pores of 0.3–0.5 μm in diameter arranged in a rectangular grid with 1 μm spacing have been made on the basis of 2.5, 3, 6 and 10 μm thick mylar films by deep X-ray lithography at the VEPP-3 storage ring. The membranes have a geometrical transparency of 10–20% and this value can be increased up to 50% and higher by using an X-ray mask with an appropriate pattern. The results of preliminary membrane testing by scanning electron microscopy and by gas conductance measurements are presented. In contrast to the traditional track membranes with random pore locations, the regular membranes have no dispersion of pore sizes caused by confluence of adjoining pores. Some possible applications of the membranes are discussed.