Optical disk mastering using optical superresolution technique

Abstract

A new laser lithography technique using the effect of optical superresolution can effectively reduce the exposed spot size on a photoresist layer, thus allowing disk mastering toward higher density using an existing light source and optics. A thin metallic mask layer deposited on the top of the photoresist layer is used to obtain a "below optical diffraction limit" linewidth on the photoresist layer. The feasibility of the laser lithography technique, as evaluated by simulation and experimental results, revealed that the linewidth on the photoresist layer could be shrunk by more than 50% of the diffraction limit of the optical system.