A stepper system for ultra-high resolution nano-lithography employs a photolithographic mask which includes a layer of an electrically conductive optically opaque material in which periodic arrays of sub-wavelength apertures are formed. The plasmonic excitation in the photolithographic mask exposed to the light of the wavelength in the range of 197 nm-248 nm, produces high resolution far-field radiation patterns of sufficient intensity to expose a photoresist on a wafer. The stepper system demonstrates the resiliency to the mask defects and ability to imprint coherent clear features of nano dimensions (45 nm-500 nm) and various shapes on the wafers for integrated circuits design. The stepper system may be adjusted to image the plane of the highest plasmonic field exiting the mask.