Image distance shift effect of the metal superlens and its applications to photolithography

We show an image distance shift effect of the metal superlens, which is that in the case in which the pattern of a mask acting as an object and the distance from the mask to a given metal superlens are fixed, the image distance of the given metal superlens is shifted to larger values with decreasing the thickness of the mask or increasing the dielectric constant of the filling material in the slits of the mask. A possible explanation of this effect is proposed. Furthermore, simulation results show that, by using the reported effect, the performance of the metal superlens lithography technique assisted by a plasmonic mirror can be significantly improved.