An overview of scanning near-field optical microscopy in characterization of nano-materials

Scanning Near-Field Optical Microscopy (SNOM) is a member of scanning probe microscopes (SPMs) family which enables nanostructure investigation of the surfaces on a wide range of materials. In fact, SNOM combines the SPM technology to the optical microscopy and in this way provide a powerful tool to study nano-structures with very high spatial resolution. In this paper, a qualified overview of diverse SNOM methods mostly based on aperture and aperture-less is presented.