Methods for the Formation of Regular Porous Structures in Polyethylene-Terephthalate Films

Three methods of obtaining regular porous structures in polyethylene-terephthalate polymer films are considered. A film is irradiated with synchrotron radiation at an X-ray lithography station through a mask based on a tantalum membrane perpendicular to its surface, followed by the chemical etching of destruction zones. To form regular porous structures, the method of polymer etching with a focused ion beam in a scanning electron microscope is used. This method enables variation of the diameter of the formed channels, the distance between them, and precludes chemical etching of the destroyed polymer, which provides a smoother pore surface. The pores are formed using nanosecond- and femtosecond-laser radiation in the nonlinear absorption mode. For femtosecond and nanosecond sources, optimal parameters of laser action on the film samples are selected, resulting in the formation of through pores in a single laser pulse.